Penetration Research Articles

Synthesis of polyesters derived from glycerol and phthalic anhydride and its application for bitumen modification

AbstractThis study introduces phthalic anhydride (P) and glycerol (G)‐based polyester as an additive for upgrading lower‐grade bitumen to higher‐grade bitumen. The different colorless polyesters were synthesized using polycondensation of P and G as a monomer in the ratio of 1:1 and polymerization time of 1, 3, 5, and 7 h. A rheological analysis was performed on all the synthesized polyesters to check their performance with respect to their use in bitumen modification. The polyesters were blended with base bitumens (VG10) to obtain the modified bitumens that were tested for the rheological and physicochemical properties and to assess the performance based on the grade quality test. The quality test of the modified bitumens includes softening point (SP), penetration (PEN), kinematic viscosity (KV), dynamic viscosity (DV), and rheological properties as per standard ASTM test methods. Based on the performance evaluation, P1G1H3 polyester was found suitable for blending with bitumen, and further study was carried out with blending of P1G1H3 with 3, 6, 10, and 15 wt%. The finding illustrates that 6.0 wt% of polyester‐modified bitumen show an enhanced SP, KV, and DV by 23.6, 86, and 30%, respectively, while decreasing the PEN by 49% with respect to VG10. Polyester blending also improved the rheological parameters in terms of deformation resistance, load‐bearing capacity, and the viscoelastic nature of bitumen. The investigation concluded that 6 wt% P1G1H3 polyester on blending in VG10 meets VG30 bitumen specification as per IS:73:2013.

Hybrid Optimization of Process Parameters in Manual Metal Arc Welding for Nanostructured Hard facing

AISI 310 stainless steel and EN24 steel were welded together using Manual Metal Arc Welding. Minitab and Design Expert software were applied to predict and optimize the results for bead width (BW) and weld penetration (PE). Total of 30 experiments were conducted according to the Box-Behnken design in RSM. Four different welding parameters current, voltage, welding speed, and root gap were employed to examine their effects on output values. The optimal conditions for BW were determined using the SN ratio, leading to an optimal parameter combination of C1-V4-W4-R4. This combination corresponds to a current of 75A, a voltage of 18V, a welding speed of 50 mm/min, and a root gap of 3 degrees. The optimal parameter value obtained from the Design Expert software were used to find the BW and PE to evaluate the weld quality. Under the optimal conditions, the supreme BW achieved was 13.994 mm, while the extreme PE reached 4.43976 mm, indicating satisfactory weld quality.

Identification of milling status based on vibration signals using artificial intelligence in robot-assisted cervical laminectomy

BackgroundWith advances in science and technology, the application of artificial intelligence in medicine has significantly progressed. The purpose of this study is to explore whether the k-nearest neighbors (KNN) machine learning method can identify three milling states based on vibration signals: cancellous bone (CCB), ventral cortical bone (VCB), and penetration (PT) in robot-assisted cervical laminectomy.MethodsCervical laminectomies were performed on the cervical segments of eight pigs using a robot. First, the bilateral dorsal cortical bone and part of the CCB were milled with a 5 mm blade and then the bilateral laminae were milled to penetration with a 2 mm blade. During the milling process using the 2 mm blade, the vibration signals were collected by the acceleration sensor, and the harmonic components were extracted using fast Fourier transform. The feature vectors were constructed with vibration signal amplitudes of 0.5, 1.0, and 1.5 kHz and the KNN was then trained by the features vector to predict the milling states.ResultsThe amplitudes of the vibration signals between VCB and PT were statistically different at 0.5, 1.0, and 1.5 kHz (P < 0.05), and the amplitudes of the vibration signals between CCB and VCB were significantly different at 0.5 and 1.5 kHz (P < 0.05). The KNN recognition success rates for the CCB, VCB, and PT were 92%, 98%, and 100%, respectively. A total of 6% and 2% of the CCB cases were identified as VCB and PT, respectively; 2% of VCB cases were identified as PT.ConclusionsThe KNN can distinguish different milling states of a high-speed bur in robot-assisted cervical laminectomy based on vibration signals. This method is feasible for improving the safety of posterior cervical decompression surgery.

A Process of Penetration Testing Using Various Tools

In the present world, information and data are the greatest assets one can possess. If one cannot secure their information from cyber-attacks, they would lose everything in the blink of an eye. Penetration testing can help reduce this cyber-risk exposure of clients' data and protect them. Penetration testing (also called "pen testing") is a part of ethical hacking that exposes the weak areas, vulnerabilities, or loopholes in the core of a PC, its networks, and its applications with the purpose of securing the system. The main idea of pen testing is to find vulnerabilities in systems and fix them before attackers can take advantage of them. These vulnerabilities are identified, exploited, and analyzed in five phases: information gathering, scanning, gaining access, maintaining access, and covering tracks. Penetration testing is done regularly in order to maintain high-security standards. As it pertains to any organization’s secrecy and privacy, this testing is also constrained by a number of legal agreements. The work provided by many researchers in the field of penetration (PEN) testing is reviewed and analyzed in this paper. This report gives a detailed description of the process and tools used to conduct penetration testing

Traveling pulses with oscillatory tails, figure-eight-like stack of isolas, and dynamics in heterogeneous media

The interplay between 1D traveling pulses with oscillatory tails (TPOs) and heterogeneities of the bump type is studied to formulate a generalized three-component FitzHugh–Nagumo system of equations. We present that stationary pulses with oscillatory tails (SPOs) form a “snaky” structure in homogeneous spaces and then TPO branches form a “figure-eight-like stack of isolas” located adjacent to the snaky structure of the SPO. Here, we adopt input resources such as the voltage-difference as a bifurcation parameter. A drift bifurcation from the SPO to TPO is observed by introducing another parameter at which these two solution sheets merge. In contrast to the monotone tail case, in the heterogeneous problem, a nonlocal interaction appears between the TPO and the heterogeneity, creating infinitely many saddle solutions and finitely many stable stationary solutions distributed across the line. The response of the TPO shows various dynamics including pinning and depinning processes along with penetration (PEN) and rebound (REB). The stable/unstable manifolds of these saddles interact with the TPO in a complex manner, creating a subtle dependence on the initial condition, and a difficulty to predict the behavior after collision even in 1D space. For the 1D case, a systematic global exploration of solution branches induced by heterogeneities (heterogeneity-induced-ordered patterns; HIOPs) reveals that HIOPs contain all the asymptotic states after collision to facilitate the prediction of the solution results without solving the PDEs. The reduction method of finite-dimensional system enables the clarification of the detailed mechanism of the transitions from PEN to pinning and pinning to REB based on a dynamical system perspective. Consequently, the basin boundary between two distinct outputs against the heterogeneities yields infinitely many successive reconnections of heteroclinic orbits among those saddles when the strength of heterogeneity increases. This causes the aforementioned subtle dependence of initial condition.

Spectral analysis for identification of plant ecosystems in Brazilian Atlantic Forest / Análise espectral para identificação de ecossistemas vegetais na Mata Atlântica Brasileira

The creation of the Guadeloupe EPA aimed to protect natural ecosystems and promote sustainable development in atlantic forest fragments existing in Pernambuco, Brazil. However, even with the State Decree formalizing these objectives, the ecosystems of the Atlantic Forest Biome present at the site suffered serious data by anthropic actions. For the study of these ecosystems, spectral analysis was an excellent channel of connection between geotechnologies and phytogeography of the site, allowing to study the location and type of vegetation in the extension of the Conservation Unit. From this perspective, the present research aimed to differentiate the atlantic forest ecosystems through spectral analysis. The results of spectral analysis allowed to indicate that in the identification of the Dense Ombrófila Forest the best specific combination is Atmospheric Penetration (PA) in its Pixel (PI) α. Mangrove in turn can be better identified in Infrared Vegetation (IVV) - Ranging from 150 to 220 Ash Levels (NC) - in pi α and also in PI β and PI γ varying in values very close to 50NC. Regarding restinga it is estimated that it can be accurately identified in Agriculture (AG), especially in pi γ, and also in Enhanced Vegetation Index (EVI) and Normalized Difference Water Index (NDWI), in all its Pixels.

Physical/Rheological Characteristics of Bitumen Modified by SBS, ZnO, TiO2 and EVA Precursors

Owing to climate conditions, heavy traffic loads, and increasing axial loads, conventional bitumen/asphalt should be modified. Bituminous materials are also vulnerable to aging during construction and service time of pavement, which will seriously affect the service performance/life of bitumen pavement. To this end, bitumen was modified using styrene-butadiene-styrene (SBS), ZnO, TiO2 and ethylene vinylacelate (EVA). Applied methodology was Mixture Design and contents of SBS, ZnO, TiO2 and EVA were considered as independent variables. Response variables followed as: G*/sin OB, G*/sin RTFO, G*/sin PAV, RV, penetration (PEN), softening, ductility, m-value and stiffness. Results of experiments of penetration degree, softening point, and ductility performed on basic bitumen without any additives were 89, 49 °C, and 137, respectively. Effects of independent variables were investigated on response variables using mathematic models and optimized compositions. SBS, ZnO, TiO2 and EVA precursors positively affected the PEN parameter. Manipulated samples possessed penetration range of 48–62 (1/10mm). Maximum softening was reached at the highest EVA and the minimum softening was detected at the largest ZnO and TiO2. Softening point ranged in 59–71 °C. SBS, ZnO, TiO2 and EVA components positively increased ductility and the largest positive effect belonged to SBS. SBS and EVA positively affected G*/sin OB response, whereas ZnO and TiO2 variables negatively decreased it. Dynamic shear rheometric (DSR) data for aged bitumens within short term periods decreased from 52 to 76 °C for all investigated samples. All mentioned modifications were performed to optimize performance of ultimate bitumen from perspectives of softening, ductility, strength, m-value, stiffness, etc.

Carbon increase and soil physical improvement in an onion no-tillage system

The no-tillage vegetable planting system (NTVPS) is a way to integrate production and soil conservation. The study was conducted on a Haplic Cambisol in the municipality of Alfredo Wagner - SC, in 2017. It aimed to evaluate physical attributes and carbon fractions of soil under consolidated NTVPS cultivation for 10 years as compared to thirty-year conventional tillage (CT) and a native forest (NF) on a Haplic Cambisol. The aspects evaluated were: total organic C, soil density (SD), total porosity (TP), macropores, micropores, aggregate stability, resistance to mechanical penetration (PR) and water infiltration into de soil. CT showed higher SD as compared to NTVPS, mainly in the 5 to 10-cm layer, whereas PR was higher in NTVPS, particularly in the 5 to 10-cm layer, thus exceeding the critical limit for this variable. Nevertheless, NTVPS showed greater accumulated water infiltration and infiltration stabilization at 20 minutes. In the native forest, infiltration was lower than that in NTVPS, and the lowest constant infiltration values occurred in CT from the beginning of the test. The NTVPS treatment showed greater efficiency in carbon storage and aggregation as compared to CT, therefore, favorable structural conditions for plant growth.

Correlation and modelling of the penetration and softening point tests of bitumen binders with a variety of physical and chemical properties

Studying bitumen has always posed a challenge to researchers owing to its extreme complexity and unique properties. To classify it commercially and to determine bitumen grade, two standard empirical tests have been adopted within the European standardized bitumen binders system [EN 12591:2009 (2009) Bitumen and bituminous binders – Specifications for paving grade bitumens]: Softening Point (SP) and Penetration (PEN). The relationship between these two tests and the physical or chemical properties of bitumen is not well understood. For the first time, this study represents an attempt to build more understanding of such a relationship through a comprehensive study of the correlation between the two standard tests and many physical and chemical properties of bitumen. A second goal is to propose some predictive models for these two tests and compare their predictive accuracy. Therefore, 13 Straight Run Vacuum Residues (SRVR) samples from different geographical origins were analyzed to measure the following parameters: Dynamic Viscosity (VisDy), Conradson Carbon Residue (CCR), C5 Asphaltenes Content (AspC5), C7 Asphaltenes Content (AspC7), Elemental Analysis (including C, H, O, N, S, Ni, and V content), Simulated Distillation (SD), Fourier-Transform Infrared Spectroscopy (FT-IR), and proton nuclear magnetic resonance spectroscopy (H-NMR). Results of studying correlations using correlation matrix and Principal Component Analysis (PCA) have emphasized the prominent effect of asphaltenes content on the other properties and the results of SP and PEN. It has also shown the potential importance of the aliphaticity/aromaticity of bitumen. Then, four models were proposed for the prediction of SP and PEN: viscosity, FT-IR, H-NMR, and multi-parameter models. Partial least squares (PLS) regression was used for building all models, except viscosity ones. All SP models, except H-NMR model, exhibited very good accuracy compared to the standard method. On the other hand, PEN was more difficult to predict than SP and only the multi-parameter model of PEN showed relatively good accuracy of prediction.

Effect of bagasse lignocellulose microfibers on sand stabilization: A laboratory study

Mulch utilization is one of the most widely used methods to: control wind erosion, stabilize sand dunes, and increase the soil resistance to shear strength. The purpose of this study was to investigate the possibility of using lignocellulose micro-fibers (LCMF) as a biological mulch to stabilize moving sand. Different levels of bagasse LCMF, 2.5, 5, and 10 gr/0.3 m 2 containing black liquor (BL) (10 gr/0.3 m 2 ), were applied on the moving sand surfaces. Mulch was sprayed in one layer and two layers on the surface. The research was conducted in a completely randomized design with three replications. To evaluate the performance of these materials, resistance to penetration (PR), shear strength (SS), germination (G), and water infiltration rate (IR) were measured and the data statistically analyzed. The results show that the highest SS and PR were observed by pure LCMF of 10 gr/0.3 m 2 layers (T10) and LCMF (10 gr/0.3 m 2 ) + BL (T13) (in two-layers) and increased the resistance to penetration 300 and 303 (Kpa) times and the shear strength 3.6 and 3.3 (N/cm 2 ) times compared to the control. The maximum IR occurred with LCMF mulch applied at 5 gr/0.3 m 2 (T2). The effect of treatments on germination was not significant and the mulches used had no adverse effect on the Haloxylon persicum . Based on parameters measured (SS, PR, G, and IR), T10 was found to be the best mulch treatment for stabilizing moving sand.

Influência dos cultivos de milho e guandu para produção de silagem na resistência do solo à penetração

O uso intensivo de máquinas agrícolas no cultivo de plantas para produção de silagem pode ocasionar a compactação do solo e comprometer o desenvolvimento das plantas. O objetivo deste trabalho foi avaliar os efeitos do cultivo de milho e guandu na resistência do solo à penetração (RP), cultivados em solo preparado de forma convencional. Os dados de RP foram obtidos por meio de um penetrômetro de impacto modelo IAA/Planalsucar, até os 0,4 m de profundidade. Foram coletadas amostras de solo para se avaliar a umidade gravimétrica do solo. Os valores de resistência mecânica do solo à penetração foram transformados em unidade padrão de pressão (MPa). O delineamento experimental empregado foi de blocos ao acaso, com dois tratamentos representados pelos cultivos de milho e guandu em área de 2000 m² cada, divididos em 10 repetições e 4 perfis analisados em cada repetição. Os valores encontrados nos dois tratamentos foram críticos ao desenvolvimento vegetal e o solo cultivado com guandu apresentou menor resistência à penetração em quase todos os estratos analisados. Os resultados obtidos demonstraram que o potencial do guandu em descompactar o solo foi superior ao do milho.

Multifractal analysis of soil penetration resistance under sugarcane cultivation

ABSTRACT Soil resistance to penetration (PR) is an indirect measure of the state of soil compaction. Thus, the objective of this study was to characterize PR in vertical profiles in an area cultivated with sugarcane using multifractal models for different relief units. The experiment was carried out in an Oxisol with a clay texture, with 6.85 ha in the municipality of Coelho Neto (Maranhão state, Brazil), where 60 sampling points were demarcated. The area was divided into four relief units (Type A &gt; 74 m, Type B from 71 to 74 m, Type C from 68 to 71 m and Type D from 65 to 68 m). The PR was measured at the 60 sampling points using an impact penetrometer, and the PR determined in the 0-0.60 m depth layer every 0.01 m. The multifractal analysis was performed considering the scale property of each profile and typified the singularity and Rènyi spectra estimated using the current method. Multifractal analysis allowed the identification of patterns at different scales and with high heterogeneity. The multifractal behavior was represented by the singularity spectrum (α), versus f(α), and the generalized dimension (Dq). The multifractal analysis allowed the differentiation between the profiles of the relief units (Types A, B, C and D), resulting in an important tool for studies of soil resistance to penetration.

Physical and Chemical Attributes of Yellow Oxisol With the Application of Cassava Wastewater After Intensive Mechanical Preparation

The objective of this work was to evaluate the effect of the application of cassava wastewater in the production of dry mass of the spontaneous vegetation and in the physical and chemical attributes of a Dystrocohesive Yellow Oxisol submitted to intensive mechanical preparation in the Bahia Rec&amp;ocirc;ncavo. The experimental design was a 2 &amp;times; 2 factorial scheme in 4 randomized blocks, the bands consisting of the intensity of the mechanical preparation of plowing followed by sorting: T0: without preparation; T1: 4 preparations; T2: 8 preparations and T3: 12 preparations; the first factor is the presence of cassava wastewater: M-with cassava wastewater; W-only water and the second factor presence or not of vegetation: CV-with vegetation and SV-without vegetation. The results of the analysis of soil attributes in the depth of 0.0-0.15 m showed that the pH, saturation by base (V%), macroporosity (Ma) and total porosity (TP) decreased linearly with the increase of the intensity of the mechanical preparation, however soil density (SD) increased. The application of cassava wastewater reduced the resistance to penetration (PR), pH and Ca2+ and V% of the soil and increased the dry mass productivity of the spontaneous vegetation and the contents of phosphor.

Physical Quality of an Oxisol in Different Agricultural Systems in Brazilian Cerrado

The soil physical quality is a way of evaluating the current condition of forest plantations that is growing in the southeast region of Mato Grosso do Sul State. In this sense, this work aimed to evaluate the impact of the forest plantations on the physical quality of an Oxisol (Haplic Acrustox) in Cerrado. The experiment was conducted in the Experimental area of the Teaching and Research Farm, of the Engineering college of Ilha Solteira (UNESP), located in the city of Selvíria-MS, situated in the conditions of the Brazilian Cerrado. The soil samples were collected at depths of 0.00-0.10; 0.10-0.20; 0.20-0.30 and 0.30-0.40 m in three areas cultivated for 30 years: area (1) Pine forest (Pinus caribaea var. hondurensis); (2) Eucalyptus forest (Eucalyptus camaldulensis); (3) Reforested ciliary forest, being used a completely randomized design, with 25 replications and 3 treatments. The analyzed attributes of the soil was: macroporosity (Ma), microporosity (Mi), total porosity (TP), bulk density (BD), real particle (RP), soil resistance to penetration (PR), gravimetric moisture (GM), volumetric moisture (VM) and sand, silt and clay contents. The three evaluated areas presented macroporosity below the critical limit (0.100 m³ m-³), thereby impairing the root development. The three evaluated areas affected the physical quality of the soil. Being the physical attributes that most influenced in the reduction of the soil physical quality was the bulk density, total porosity, microporosity, macroporosity and soil resistance to penetration.

Resistencia mecánica del suelo a la penetración de raíces y forma de la raíz reservante de la batata a partir del descriptor de Huamán

´Se estableció un ensayo para determinar la influencia de la resistencia mecánica a la penetración de raíces (RP), en un suelo afectado por la labranza y por la distancia de siembra, sobre la forma de la raíz reservante del cultivo batata (Ipomoea batatas (L.) Lamb). El diseño del experimento se basó en un arreglo en franjas, donde los sistemas de labranza (SL) fueron asignados a las parcelas grandes y las densidades de siembra (DS) a las franjas. Los SL consistieron en: 1) labranza vertical profunda con cincel y 3 pases de rastra (LC); 2) profunda con arado de disco y 3 pases de rastra (LA); 3) media con 3 pases de rastra de disco (LCo); y 4) mínima con un pase de rastra de disco (LM). Con 4 profundidades de trabajo de 18, 23, 12 y 7 cm, respectivamente. Las DS fueron de 0,25 cm (D1) y 0,15 cm (D2) en la hilera. La RP fue superior en los estratos del suelo a profundidades de 5 a 15 y 15 a 25 cm en los tratamientos de LM, (44 y 37%, respectivamente), respecto al promedio observado en el resto de los tratamientos en los estratos mencionados. Hubo escasa diferenciación entre los sistemas de labranza media y profunda (LCo, LC, LA) para RP. Se encontraron formas redondeadas preferiblemente en los tratamientos de LA; elíptica y redonda, elíptica bajo LC; y redonda y redonda elíptica en LCo y LM. No se observó una mayor restricción del crecimiento longitudinal de la raíz del cultivo en el suelo con mayor dureza bajo los tratamientos de LM. Esto en parte explicado a partir de los valores no limitantes a la penetración de raíces (&lt; 2 MPa) del suelo en los diferentes tratamientos.

STUDIES OF OLEORESINS AS PENETRATION ENHANCER FOR TRANSDERMAL PATCH OF KETOPROFEN

The study deals wit h the effect of oleoresins (nutmeg, capsicum, coriander and garlic) as penet rat ion enhancer for t ransdermal pat ch of ketoprofen. The t ransdermal patch prepared by mercury subst rate technique and evaluated. I n vit ro release was found t o be more than 60% through rat skin and 70% through cellophane membrane in capsicum oleoresin. In vivo study indicated that capsicum had 80.56 edema inhibit ions and t ransdermal patch without penet rat ion enhancer had 65.84 edema inhibit ions. This indicated that the formulat ion containing oleoresin capsicum had high % edema inhibit ion. The more skin permeability and greatest flux of ketoprofen was obtained significantly by capsicum oleoresin. From Overall study, it can be concluded that to deliver the drug through the skin, penetration enhancer play a vital role. So to deliver the drug into systemic circulation at predetermined rate by transdermal therapeutic system of Ketoprofen, using natural oleoresins as penetration enhancer. In nutshell the oleoresins like Oleoresin nutmeg, Oleoresin capsicum, Oleoresin garlic, Oleoresin coriander shows penet rabilit y and drug wit h maximum flux. Amongst this oleoresin capsaicin shows bet ter performance as penetration enhancer.

Minimizing Water Invasion into Kazhdumi Shale Using Nanoparticles

Fluid invasion from water-based drilling mud (WBDM) into the shale formations causes swelling, high pressure zone near the wellbore wall, and even tually wellbore instability problems during drilling operations. For the stability of the wellb ore, physical plugging of nanoscale pore throats co uld be considered as a logical approach toward avoiding the fluid invasion into the shale formation. This paper reports the effect of silica nanoparticles (N Ps) as a physical sealing agent on the water invasi on into Kazhdumi shale. To this end, pressure penetrat ion apparatus was implemented. Typical WBDM in contact with Kazhdumi shale at different concent rations of NPs with different sizes was studied. The results indicated that the addition of NPs to t he WBDM decreased water invasion into Kazhdumi shale. WBDM having 10 wt.% of 25 nm NPs reduced fluid invasion up to 72.76%.

ABC transporter PEN3/PDR8/ABCG36 interacts with calmodulin that, like PEN3, is required for Arabidopsis nonhost resistance.

Nonhost resistance (NHR) is the most prevalent form of plant immunity. In Arabidopsis, NHR requires membrane-localized ATP-binding cassette (ABC) transporter PENETRATION (PEN) 3. Upon perception of pathogen-associated molecular patterns, PEN3 becomes phosphorylated, suggestive of PEN3 regulation by post-translational modification. Here, we investigated the PEN3 protein interaction network. We probed the Arabidopsis protein microarray AtPMA-5000 with the N-terminal cytoplasmic domain of PEN3. Several of the proteins identified to interact with PEN3 invitro represent cellular Ca(2+) sensors, including calmodulin (CaM) 3, CaM7 and several CaM-like proteins, pointing to the importance of Ca(2+) sensing to PEN3-mediated NHR. We demonstrated co-localization of PEN3 and CaM7, and we confirmed PEN3-CaM interaction invitro and invivo by PEN3 pull-down with CaM Sepharose, CaM overlay assay and bimolecular fluorescence complementation. We also show that just like in pen3, NHR to the nonadapted fungal pathogens Phakopsora pachyrhizi and Blumeria graminis f.sp.hordei is compromised in the Arabidopsis cam7 and pen3 cam7 mutants. Our study discloses CaM7 as a PEN3-interacting protein crucial to Arabidopsis NHR and emphasizes the importance of Ca(2+) sensing to plant immunity.

MODELING OF SOIL LOAD-BEARING CAPACITY AS A FUNCTION OF SOIL MECHANICAL RESISTANCE TO PENETRATION

Estimation of soil load-bearing capacity from mathematical models that relate preconsolidation pressure (σp) to mechanical resistance to penetration (PR) and gravimetric soil water content (U) is important for defining strategies to prevent compaction of agricultural soils. Our objective was therefore to model the σp and compression index (CI) according to the PR (with an impact penetrometer in the field and a static penetrometer inserted at a constant rate in the laboratory) and U in a Rhodic Eutrudox. The experiment consisted of six treatments: no-tillage system (NT); NT with chiseling; and NT with additional compaction by combine traffic (passing 4, 8, 10, and 20 times). Soil bulk density, total porosity, PR (in field and laboratory measurements), U, σp, and CI values were determined in the 5.5-10.5 cm and 13.5-18.5 cm layers. Preconsolidation pressure (σp) and CI were modeled according to PR in different U. The σp increased and the CI decreased linearly with increases in the PR values. The correlations between σp and PR and PR and CI are influenced by U. From these correlations, the soil load-bearing capacity and compaction susceptibility can be estimated by PR readings evaluated in different U.

Mutant Allele-Specific Uncoupling of PENETRATION3 Functions Reveals Engagement of the ATP-Binding Cassette Transporter in Distinct Tryptophan Metabolic Pathways.

Arabidopsis (Arabidopsis thaliana) penetration (PEN) genes quantitatively contribute to the execution of different forms of plant immunity upon challenge with diverse leaf pathogens. PEN3 encodes a plasma membrane-resident pleiotropic drug resistance-type ATP-binding cassette transporter and is thought to act in a pathogen-inducible and PEN2 myrosinase-dependent metabolic pathway in extracellular defense. This metabolic pathway directs the intracellular biosynthesis and activation of tryptophan-derived indole glucosinolates for subsequent PEN3-mediated efflux across the plasma membrane at pathogen contact sites. However, PEN3 also functions in abiotic stress responses to cadmium and indole-3-butyric acid (IBA)-mediated auxin homeostasis in roots, raising the possibility that PEN3 exports multiple functionally unrelated substrates. Here, we describe the isolation of a pen3 allele, designated pen3-5, that encodes a dysfunctional protein that accumulates in planta like wild-type PEN3. The specific mutation in pen3-5 uncouples PEN3 functions in IBA-stimulated root growth modulation, callose deposition induced with a conserved peptide epitope of bacterial flagellin (flg22), and pathogen-inducible salicylic acid accumulation from PEN3 activity in extracellular defense, indicating the engagement of multiple PEN3 substrates in different PEN3-dependent biological processes. We identified 4-O-β-D-glucosyl-indol-3-yl formamide (4OGlcI3F) as a pathogen-inducible, tryptophan-derived compound that overaccumulates in pen3 leaf tissue and has biosynthesis that is dependent on an intact PEN2 metabolic pathway. We propose that a precursor of 4OGlcI3F is the PEN3 substrate in extracellular pathogen defense. These precursors, the shared indole core present in IBA and 4OGlcI3F, and allele-specific uncoupling of a subset of PEN3 functions suggest that PEN3 transports distinct indole-type metabolites in distinct biological processes.