Cap Length Research Articles

Improved desorption/ionization and ion transmission in surface scanning by direct analysis in real time mass spectrometry.

Modifications to the Direct Analysis in Real Time mass spectrometry (DART-MS) interface, its source cap and transfer tube were necessary to obtain highest efficiency in desorption and ionization from the sampling surface and in ion transmission into the MS system. These issues are crucial for the trace analysis of any surface and the hyphenation of high-performance thin-layer chromatography (HPTLC) with DART-MS. The ion source mounting was modified to enable short source caps to be utilized in combination with a short transfer tube. The grid voltage contact section was readjusted to increase the intensity of the metastable gas stream towards the substrate. Eighteen different cap and two transfer tube geometries (including gas-stream focusing), along with the influence of their distance from the mass spectrometer glass capillary, were investigated for best signal intensity. Using shortened source caps with staged inner bore, a transfer tube with gas-stream focusing and an optimized mounting geometry for DART-MS scanning along five identical deposited bands (600 ng each) of butyl 4-hydroxybenzoate, an average signal precision of 3.6% was obtained and the signal intensity was increased by a factor of 34. The width of the gas impact area did not exceed 1.5 mm and the smallest FWHM was determined to be 0.9 mm. The desorption strength, ionization efficacy and ion transmission were improved significantly giving increased detectability using this further modified DART-MS interface with reduced cap length and optimum transfer tube geometry. The resolution was comparable with state-of-the-art densitometry. With this setup, reliable HPTLC surface scanning is possible, even for substance amounts in the low-nanogram range.

Finite-element analysis of a piled machine foundation

A case study using finite-element software for the dynamic analysis and structural design of a machine foundation on piles in homogeneous sandy soil is reported. A parametric study was carried out to investigate the effect of the foundation geometry, the amplitude and frequency of the dynamic load, and the damping ratio. It is concluded that as the pile cap thickness increases the oscillation of displacement decreases due to material damping inherent in the concrete of the pile cap. There is a limit of the pile cap size at which its stiffness governs its dynamic response. Above this size the weight of the pile cap overrides its stiffness effect, and the additional weight leads to an increase in pile displacement. When the pile group size increases, the frequency at which maximum displacement occurs increases, and hence the system becomes more stable against resonance. In the case of changing the pile spacing, the maximum moment factor IM is always at the pile cap centre, where the load is applied. This factor increases when the pile spacing increases. The dimensionless displacement factor Iz decreases markedly as the pile cap length increases, reflecting the increase in displacement with pile cap length.

Role of salicylic acid in phosphite-induced protection against Oomycetes; a Phytophthora cinnamomi - Lupinus augustifolius model system

Phosphite is used to control Oomycetes in a wide range of horticultural and native plant species worldwide. However, phosphite can be phytotoxic, and some pathogens have exhibited a reduction in the effectiveness of phosphite due to prolonged use. In this study, salicylic acid (SA) was investigated as an alternative, or supplementary, treatment to be used to protect plant species. With the use of aeroponics chambers, foliar application of phosphite, SA, and phosphite/SA to Lupinus augustifolius was assessed in relation to root tip damage, in planta phosphite and SA concentration and lesion development. Both phosphite and SA were measurable at the root tip within 24 h of application, and all treatments significantly (P ≤ 0.05) reduced the lesion length at 7 days. However, while phosphite and SA application increased the in planta SA concentration, phosphite caused significantly more damage to the root tip by reducing root cap layers and length than the SA, or phosphite/SA application. This study supports the notion that phosphite-induced sensitivity may be SA-dependent, as both phosphite and SA were found to control P. cinnamomi and stimulate SA accumulation. A combination of phosphite and SA may be more beneficial to plants if it can reduce phytotoxic effects and reduce the chance of pathogen sensitivity to phosphite.

In vitro and in vivo evaluations of a novel pulsed and controlled osmotic pump capsule

Objective: For better treatment of circadian cardiovascular events, a novel Propranolol hydrochloride (PNH) delayed-release osmotic pump capsule was developed.Methods: The capsule body was designed of asymmetric membrane and the capsule cap was made impermeable. The physical characteristics of capsule body walls and membrane permeability were compared among different coating solutions.Results: The formulation with the glycerin and diethyl phthalate (DEP) ratio of 5:4 appeared to be the best. The lag time and subsequent drug release were investigated through assembling the capsule body with capsule caps of different length. WSR N-10 was chosen as the suspending for its moderate expanding capacity. The influence of factors (WSR N-10 content, NaCl content and capsule cap length) on the responses (lag time and drug release rate) was evaluated using central composite design-response surface methodology. A second-order polynomial equation was fitted to the data and actual response values were in good accordance with the predicted ones. The optimized formulation displayed complete drug delivery, zero-order release rate with 4-h lag time. The results of in vivo pharmacokinetics in beagle dogs clearly suggested the controlled and sustained release of PNH from the system and that the relative bioavailability of this preparation was about 1.023 comparing the marketed preparation.Conclusions: These results indicate that by the adjustment of capsule cap length, PNH could be developed as a novel pulsatile and controlled drug delivery system.

Identification of high-risk plaques associated with peri-procedural myocardial injury following elective percutaneous coronary intervention: Assessment by high-sensitivity troponin-T measurements and optical coherence tomography

A worse prognosis of peri-procedural myocardial injury (PMI) following percutaneous coronary intervention (PCI) has been reported in patients displaying an isolated elevation of cardiac troponin-T (TnT) or troponin-I [1,2]. Highly sensitive assay for TnT (hs-TnT) is newly developed, permitting measurement of TnT than those measurable limit with conventional assays [3,4]. Thus, procedural changes in TnT values following PCI using the hs-TnT assay may identify more minute myocardial injury. Optical coherence tomography (OCT) with high-resolution images (≈15 μm) allows detailed information such as fibrous cap thickness, and lipid distribution of the atherosclerotic plaque in vivo [5]. Therefore, this study has focused on precise assessments for PMI and lesion characteristics using both the hs-TnT measurements and OCT imaging. We enrolled 79 patients (59 males, age range: 42 to 86 years) who underwent elective coronary stent implantationwith OCTguidance for de novo atherosclerotic lesions. All patients were diagnosed as having stable angina pectoris (SAP) defined as a positive stress test for myocardial ischemia and no change in clinical symptoms within 4 weeks. The quantitative coronary angiography (QCA) findings were analyzed with a computer-assisted, automated edge detection algorithm(CMS,MEDIS, Nuenen, TheNetherlands). TheOCTprocedure has been previously reported [5]. Characterizations of the plaque components, such as lipid, fibrous, or calcified tissue and thrombus were validated based on the established criteria [6]. For all images with an OCT-determined lipid plaque, the angle of lipid tissue (AL), thinnest fibrous cap thickness (TFCT) and length of lipid tissue (LL) were measured as previously reported [5]. Blood samples were obtained before PCI and from 18 to 24 h following PCI. Serum hs-TnT was measured using an electrochemiluminescence pre-commercial immunoassay (Roche Diagnostics Ltd, Rotkreuz, Switzerland) [3]. According to the recent universal definition, the current study defined PMI as hsTnT values increased more than three times the 99th percentile upper reference limit (0.014 ng/ml) during PCI [7]. The patientswere divided into two groups, PMI and non-PMI groups. Thereafter, we analyzed which factors correspond to PMI by considering the patients' demographics, angiographic findings or lesion characteristics, and procedures. All statistical analyses were performed using the SPSS software program (version 11.0.1, SPSS Inc., Chicago, IL) and the MedCalc software package (version 10.1.4, MedCalc Software, Mariakerke, Belgium). A univariate logistic regression analysis was performed to obtain the odds ratio for PMI. Thereafter, a multivariate logistic regression analysis was performed using the variables with P values b 0.10 in the univariate analysis for examining their independent association with PMI. The receiver operating characteristic (ROC) curve analyseswereperformed to examine the ability of the OCTfindings to identify subjects at high-risk for PMI. All statistical tests were 2-sided, and a P value b 0.05 was considered to be significant. The mean patient age was higher than that of non-PMI group (71.0 ± 10.9 vs. 65.2 ± 9.7, P = 0.016), while the other baseline characteristics including coronary risk factors, prescription of pharmacological agents, lipid profile, estimated glomerular filtration rate or ejection fraction did not differ significantly between the groups. There were significant differences in the American Heart Association/American College of Cardiology's (AHA/ACC) classification (P = 0.023) and bifurcation lesions between the groups (20% vs. 5%, P = 0.013). Other angiographic parameters such as reference vessel diameter, minimum lumen diameter, or diameter stenosis were not different between the 2 groups. In a univariate logistic regression analysis (Table 1), age, AHA/ACC classification, thrombus, plaque rupture/fissure and each quartile increment in the AL, TFCT, and LL had a significantly increased odds ratio for PMI, and a International Journal of Cardiology 168 (2013) 2860–3148

Mechanochemical Modeling of Dynamic Microtubule Growth Involving Sheet-to-Tube Transition

Microtubule dynamics is largely influenced by nucleotide hydrolysis and the resultant tubulin configuration changes. The GTP cap model has been proposed to interpret the stabilizing mechanisms of microtubule growth from the view of hydrolysis effects. Besides, the growth of a microtubule involves the closure of a curved sheet at its growing end. The curvature conversion from the longitudinal direction to the circumferential direction also helps to stabilize the successive growth, and the curved sheet is referred to as the conformational cap. However, there still lacks theoretical investigation on the mechanical–chemical coupling growth process of microtubules. In this paper, we study the growth mechanisms of microtubules by using a coarse-grained molecular method. First, the closure process involving a sheet-to-tube transition is simulated. The results verify the stabilizing effect of the sheet structure and predict that the minimum conformational cap length that can stabilize the growth is two dimers. Then, we show that the conformational cap and the GTP cap can function independently and harmoniously, signifying the pivotal role of mechanical factors. Furthermore, based on our theoretical results, we describe a Tetris-like growth style of microtubules: the stochastic tubulin assembly is regulated by energy and harmonized with the seam zipping such that the sheet keeps a practically constant length during growth.

Polymerization of actin filaments coupled with adenosine triphosphate hydrolysis: Brownian dynamics and theoretical analysis

Polymerization dynamics of single actin filaments coupled with adenosine triphosphate (ATP) hydrolysis is investigated via both theoretical analysis and Brownian dynamics simulations. Brownian dynamics simulations have been applied recently to study the growth behaviors of long filaments as a function of the free actin monomer concentrations, C(T), which is found to be in agreement with the associated experiments. In the present study, both ATP cap length and length diffusivity are studied as a function of the free ATP-actin monomer concentrations, C(T). The exact analytical expressions are found to be in perfect consistency with Brownian dynamics simulations. Likewise, we find that the length diffusion coefficient is peaked near the critical concentration, C(T,cr). It is, therefore, expected that the dependence of length diffusivity on ATP-actin monomer concentrations is utilized to analyze the surprising experiments on the length fluctuations of individual actin filaments.

Cofilin Tunes the Nucleotide State of Actin Filaments and Severs at Bare and Decorated Segment Boundaries

Actin-based motility demands the spatial and temporal coordination of numerous regulatory actin-binding proteins (ABPs), many of which bind with affinities that depend on the nucleotide state of actin filament. Cofilin, one of three ABPs that precisely choreograph actin assembly and organization into comet tails that drive motility in vitro, binds and stochastically severs aged ADP actin filament segments of de novo growing actin filaments. Deficiencies in methodologies to track in real time the nucleotide state of actin filaments, as well as cofilin severing, limit the molecular understanding of coupling between actin filament chemical and mechanical states and severing. We engineered a fluorescently labeled cofilin that retains actin filament binding and severing activities. Because cofilin binding depends strongly on the actin-bound nucleotide, direct visualization of fluorescent cofilin binding serves as a marker of the actin filament nucleotide state during assembly. Bound cofilin allosterically accelerates P(i) release from unoccupied filament subunits, which shortens the filament ATP/ADP-P(i) cap length by nearly an order of magnitude. Real-time visualization of filament severing indicates that fragmentation scales with and occurs preferentially at boundaries between bare and cofilin-decorated filament segments, thereby controlling the overall filament length, depending on cofilin binding density.

The effect of the interaction of varying chicken manure supplement levels with three different solid sisal wastes substrates on sporocarp cap lengths and diameters, stipe lengths and diameters and dry weights of C. cinereus (Schaeff)S.Gray s.lat

The effect of the interaction of varying chicken manure supplement levels with three different solid sisal wastes substrates on sporocarp cap lengths and diameters, stipe lengths and diameters and dry weights of Coprinus cinereus (Schaeff) S. Gray s.lat Coprinus cinereus (Schaeff) S. Gray s.lat is an indigenous Tanzanian edible and medicinal mushroom, which grows in the wild on decomposed sisal wastes heaps. In the laboratory, it was cultivated on three types of sisal wastes substrates each supplemented with varying chicken manure concentrations 0, 5, 10, 15, 20 and 25% using solid-state fermentation bioreactors. The results showed that the interaction of sisal dust, sisal fibres and sisal decortications leaves wastes substrates with chicken manure at varying concentrations, produced a highly significant effect (p < 0.05) on cap lengths and diameters, stipe lengths and diameters and dry weights of C. cinereus (Schaeff) S. Gray s.lat. The interactions of sisal dust waste with 5% chicken manure concentration induced longest mean cap length and widest mean cap diameter. On the other hand, the interaction of sisal leaves decortications wastes with 25% chicken manure concentration produced heaviest sporocarps mean dry weight. These findings for the first time illustrate importance of chicken manure supplementation in C. cinereus (Schaeff) S. Gray s.lat cultivation on sisal decortications wastes substrates. Key words : Coprinus cinereus, chicken manure, solid sisal wastes, sporocarps, pileus, stipe.

Recoil after Severing Reveals Stress Fiber Contraction Mechanisms

Stress fibers are cellular contractile actomyosin machines central to wound healing, shear stress response, and other processes. Contraction mechanisms have been difficult to establish because stress fibers in cultured cells typically exert isometric tension and present little kinetic activity. In a recent study, living cell stress fibers were severed with laser nanoscissors and recoiled several μm over ∼5 s. We developed a quantitative model of stress fibers based on known components and available structural information suggesting periodic sarcomeric organization similar to striated muscle. The model was applied to the severing assay and compared to the observed recoil. We conclude that the sarcomere force-length relation is similar to that of muscle with two distinct regions on the ascending limb and that substantial external drag forces act on the recoiling fiber corresponding to effective cytosolic viscosity ∼104 times that of water. This may originate from both nonspecific and specific interactions. The model predicts highly nonuniform contraction with caps of collapsed sarcomeres growing at the severed ends. A directly measurable signature of external drag is that cap length and recoil distance increase at intermediate times as t1/2. The severing data is consistent with this prediction.

Dynamics of an idealized model of microtubule growth and catastrophe.

We investigate a simple dynamical model of a microtubule that evolves by attachment of guanosine triphosphate (GTP) tubulin to its end, irreversible conversion of GTP to guanosine diphosphate (GDP) tubulin by hydrolysis, and detachment of GDP at the end of a microtubule. As a function of rates of these processes, the microtubule can grow steadily or its length can fluctuate wildly. In the regime where detachment can be neglected, we find exact expressions for the tubule and GTP cap length distributions, as well as power-law length distributions of GTP and GDP islands. In the opposite limit of instantaneous detachment, we find the time between catastrophes, where the microtubule shrinks to zero length, and determine the size distribution of avalanches (sequence of consecutive GDP detachment events). We obtain the phase diagram for general rates and verify our predictions by numerical simulations.

Optimum shape for buckling and post-buckling behavior of a laminated composite panel with I-type stiffeners

A shape optimization of stiffener was conducted to increase buckling load or failure load with stiffened laminated composite panel of I-type under compression loading. Design variables are cap length, web length, and/or thickness under the constraint of volume constancy. The objective function is buckling load and failure load of post-buckling based on Tsai-Hill theory using ABAQLJS 5.8 for analysis and Optimizer on Broydon-Fletcher Goldfarb-Sharno Method and Augmented Lagrange Multiplier Method. The effects of relative length of a web and a cap of stiffener on buckling load and failure load of post-buckling were investigated with the results of optimum design.

Sexual dimorphism in the birds from southern Veracruz, Mexico, and other localities. III. Wilson's Warbler (Wilsonia pusilla)

Abstract Using museum specimens from Mexico, Canada, and the western United States, we examined sexual dimorphism in the Wilson's Warbler (Wilsonia pusilla), a Nearctic-Neotropic migrant (Passeriformes: Parulidae). On average, males had longer tails, wing chords, and eighth and ninth primaries than females. Three methods for quantifying cap plumage showed that differences in cap size and pattern alone could not definitively separate the sexes. Discriminant functions are presented for sexing individuals using cap category, cap length, wing chord, tail length, and ninth primary length. More specific functions are provided for samples from Alaska and eastern Mexico. For each group, equations are included for assigning individual probabilities of belonging to either sex.

Structural Changes and Aluminium Distribution in Maize Root Tissues

Growth and structural responses of primary roots of Zea mays L. to aluminium chloride were studied. The treatment of seedlings with 50 &micro;M AlCl3 resulted in high accumulation of Al, partial inhibition of root growth, occurrence of surface lesions in peripheral tissues, root thickening caused by expansion of inner cortical cells, reduced root cap length, extensive vacuolation, cell distortion, and increased synthesis of callose within 24 h.

Somatic embryogenesis in Norway spruce: Anatomical study of embryo development and influence of polyethylene glycol on maturation process

The sequence of the developmental stages during somatic embryo maturation in Norway spruce ( Picea abies (L.) Karst.) was described for a maturation medium (containing abscisic acid) and for the same medium supplemented with 3.75 and 7.5 % polyethylene glycol (PEG-4000). Embryo maturation was accomplished after six weeks of cultivation on the PEG-free medium, and prolonged cultivation resulted in a higher frequency of irregularly developing embryos. The addition of 3.75 % PEG increased the speed of the maturation process by two weeks and caused changes in the morphometric characteristics, e.g. an increase in embryo length (approx. 30–40 %). PEG at a concentration of 7.5 % did not further speed up the process. In addition, the size of the embryos remained approximately the same, and only the root cap length increased by approx. 40 % as compared to the 3.75 % PEG variant. On the other hand, some morphological abnormalities occurred (e.g. rows of dead cells and ruptures in the center of embryos), which are unambiguously negative for further germination. As the developmental process improved, the number of subcultivations needed was lowered and thus the probability of damage due to mechanical irritation also decreased. This has been attributed to the undoubtedly positive effect of the presence of 3.75 % PEG in the medium. Based on all of the obtained results, we concluded that, of all the treatments tested, the medium supplied with 3.75 % PEG proved to be the most beneficial for embryo development of the studied genotype of Norway spruce.

Adaptation of Cortical Collecting Duct (CCD) Beta Intercalated Cells(β-ICCs) to Metabolic Acidosis • 1824

Alpha and beta ICCs of the renal collecting duct play a significant role in the regulation of acid-base transport and both have previously been shown through functional studies to adapt under conditions of metabolic acidosis.β-ICCs secrete bicarbonate via an apical Cl-HCO3 exchanger and basolateral H+ pump. They are further characterized by two unique surface antigen markers -- an apical glycoprotein which binds peanut agglutinin (PNA) and one which binds monoclonal antibody (Mab) B63, a probe that we have previously shown inhibits Cl-HCO3 exchange (AJP 266: F901, 1994). β-ICCs adapt to metabolic acidosis by decreasing bicarbonate secretion. We hypothesize that the adaptation may involve cell surface remodeling of β-ICCs. Isolated CCDs from control and one day acid-fed rabbits were perfused with Mab B63 and two fluorescent probes (FITC-PNA and Texas Red coupled anti-mouse secondary antibody vs. Mab B63). After microperfusion of the CCDs, labeling of β-ICCs, and fixation in a 3D state, specimens were examined using fluorescence microscopy. PNA(+) and B63(+) cells exhibited coincident staining under control and acid-fed conditions. The pattern of staining resembled a cap when the cell's luminal surface was orthogonal to the plane of the camera. Cell surface area was assessed by measuring cap lengths. With acid treatment, the cap length decreased in both the PNA(+) cells (7.2 ± 0.3 μm, n=27 cells vs. 5.6± 0.3, n=14; p<0.01) and B63(+) cells (7.8 ± 0.3, n=33 vs. 5.6 ± 0.3, n=19; p<0.01). The number of PNA(+) cells per high power field identified in one focal plane of the tubule also decreased with acid treatment (5.6 ± 0.3 cells per field, n=17 fields vs. 3.7 ± 0.3, n=7; p<0.01) as did the number of B63(+) cells (6.1 ± 0.3, n=15 vs. 3.5 ± 0.7, n=8; p<0.01). Findings of decreased B63 staining with acid treatment were confirmed with immunocytochemistry on PLP fixed tissue sections. These studies indicate that the β-ICC adaptation to metabolic acidosis involves apical cell surface remodeling probably by endocytosis. The observed decrease in bicarbonate secretion with acidosis may be mediated by internalization of apical Cl-HCO3 exchangers or associated regulatory proteins. (Data reported as mean ± SEM.)

Mouse molar morphogenesis revisited by three-dimensional reconstruction. II. Spatial distribution of mitoses and apoptosis in cap to bell staged first and second upper molar teeth.

Tooth morphogenesis is a complex multifactorial process in which differential mitotic activities and cell death play important roles. Upper first (m1) and second (m2) molars from mouse embryos were investigated from early cap to bell stage. m2 differed from m1 by delayed origin of the enamel grooves delimiting the protrusion of the cap bottom towards the dental papilla, and retardation of the enamel knot formation. The width of the m2 enamel organ was conspicuously smaller during cap formation and length remained smaller throughout the period of observation. Formation of the cap depression was comparable in m1 and m2, however margins delimiting the enamel organ cavity arose in m1 and m2 as mirror images. Attempts were made to correlate changes in the distribution of apoptotic cells and bodies and/or mitoses with morphogenesis. These cellular activities were recorded from histological sections and represented in space using computer-assisted three-dimensional reconstructions. Mitoses in the epithelial compartment were associated with the development of the cervical loop. In the mesenchyme of m1 at early bell stage, a postero-anterior increasing gradient of mitoses was observed which might be correlated with the anterior growth of the molar. Cells in the enamel knot demonstrated a high level of apoptosis, retarded in m2, but absolutely no division. Apoptotic processes were also involved in the anterior delimitation of the m1 epithelium. Apoptosis might correspond to the programmed destruction of cells whose function had to be suppressed or whose potential activity had to be avoided.

Analysis of Parameters Influencing Stresses in the Solder Joints of Leadless Chip Capacitors

The purpose of this study was to evaluate parameters such as solder joint standoff and fillet heights, termination cap length, chip eccentricity, chip rotation, etc. that influence stresses in the solder joints as well as the leadless chip capacitors. This analysis covers COG and X7R ceramic chip capacitors on multi-layer FR-4, and G-30 PWB or Alumina substrates. From the values of the stresses computed, it appears that (i) the stand-off height should be at least 100μm (.004 in.) (ii) the solder fillet height should be around half the chip thickness, (iii) the chip eccentricity on the mounting pad should be restricted to 8 percent of the chip length and (iv) chip rotation should be within 3.5 deg, while maintaining minimum solder stand-off height of 100μm (0.004 in.). The recommendations given here should be used only as preliminary design guidelines and not as a substitute for design and analysis or the requirements of manufacturing standards.

Path-coefficient analysis of anatomical characters affecting peg strength in groundnut

Correlation and path-coefficient analysis for anatomical characters affecting peg strength was carried out in eleven strains of groundnut. Bundle cap length and number of xylem vessels per vascular bundle showed a significant positive correlation with peg strength. Path-coefficient analysis revealed that bundle cap length had the highest direct positive effect on peg strength whereas number of xylem vessels per vascular bundle played only a minor role directly. All the characters positively affected peg strengh in an indirect manner mostly via bundle cap lengh. All other direct effects and such indirect effects where bundle cap length was not involved were found to be unimportant. Thus bundle cap length emerged as a reliable anatomical character which can serve as a selection criterion in breeding cultivars with strong pegs to reduce harvesting losses in groundnut.

Importance of the cap in maize root growth

A large population of primary roots of Zea mays (cv. LG 11) was selected for uniform length at zero time. Their individual growth rates were measured over an 8-h period in the vertical position (in humid air, darkness). Three groups of these roots with significantly different growth rates were then chosen and their cap length was measured. It was found that slowly growing roots had long caps whereas rapidly growing roots had short caps. The production by the cap cells of basipetally transported growth inhibitors was tested (biologically by the curvature of half-decapped roots) and found to be significantly higher for longer root caps than that for shorter ones.