Frequency Distribution Of Width Research Articles

Constraining the Size of the Circumgalactic Medium Using the Transverse Autocorrelation Function of C iv Absorbers in Paired Quasar Spectra

The circumgalactic medium (CGM) plays a vital role in the formation and evolution of galaxies, acting as a lifeline between galaxies and the surrounding intergalactic medium. In this study, we leverage a unique sample of quasar pairs to investigate the properties of the CGM with absorption line tomography. We present a new sample of medium-resolution Keck/ESI, Magellan/MagE, and VLT/XSHOOTER spectra of 29 quasar pairs at redshift 2 < z < 3. We supplement the sample with additional spectra of 32 pairs from the literature, creating a catalog of 61 quasar pairs with angular separations between 1.″7 and 132.″9 and projected physical separations (r ⊥) between 14 kpc and 887 kpc. We construct a catalog of 906 metal-line absorption doublets of C iv (λλ1548, 1550) with equivalent widths ranging from 6 m Å ≤ W r,1550 ≤ 2053 m Å. The best-fit linear model to the log-space equivalent width frequency distribution () of the sample yields coefficients of m = −1.44 ± 0.16 and b = −0.43 ± 0.16. To constrain the projected extent of C iv, we calculate the transverse autocorrelation function. The flattening of the autocorrelation function at low r ⊥ provides a lower limit for the coherence length of the metal enriched CGM—on the order of 200 h −1 comoving kpc. This physical size constraint allows us to refine our understanding of the metals in the CGM, where the extent of C iv in the CGM depends on gas flows, feedback, timescale of metal injection and mixing, and the mass of the host galaxies.

Biological condition and carapace width frequency distribution of blue swimming crabs (Portunus pelagicus) in Gresik and Lamongan, East Java

Crabs, including the blue swimming crab (Portunus pelagicus), are one of the top five Indonesian fisheries export commodities. The blue swimming crab (BSC) is captured by various fishing gears that are indicated to threaten the sustainability of BSC resources. The aims of this study were to determine the biological condition of BSC by fishing gear, especially carapace width and weight relationship; sex composition and berried or non-berried female (BEF/NBEF); and carapace width distribution. BSC samples were randomly collected from four fishing bases in Gresik and Lamongan, East Java, Indonesia, from July to September 2018. The study found allometric and isometric BSC growth patterns at Gresik and Lamongan, respectively. Sex ratio of male and female crabs was balanced (1:1) with 16% of BEF in Gresik, while in Lamongan, there were more females than males (1:1.6) with 20% of BEF. Overall, catches were dominated by the size class with 11-12 cm carapace width and 70-90 g in weight. The carapace width distribution of indicated that catches from traps were dominated by BSC with of carapace width >10 cm (94%), (according to Ministerial Decree of Marine Affairs and Fisheries number 56/2016, >10 cm of carapace width is the legal size for BSC capture). Meanwhile, BSC catches from gillnets and mini trawls comprised 69% and 52% in the legal size class (>10 cm carapace width), respectively. Promoting traps as a BSC fishing gear can support the implementation of the ministerial decree in the field.

Larvae of trap-jaw ants, Odontomachus Latreille, 1804 (Hymenoptera: Formicidae): morphology and biological notes

This study aims to contribute to the neglected topic of larval biology in ants. The number of larval instars for three different species of trap-jaw ants, Odontomachus meinerti Forel, 1905, Odontomachus bauri Emery, 1892, and Odontomachus brunneus (Patton, 1894) was estimated to three based on the maximum width frequency distributions of head capsules from worker and male larvae. The obtained number of larval instars was smaller than from a previous report with another species in the genus, indicating possible interspecific variation. Larvae of different sexes and instars among the three different species were generally identical, differing merely by relative dimensions and patterns of hair distribution. Dorsal doorknob protuberances were recorded for the first time in the genus, and observed being used to fix larvae onto nest walls. From observing several individuals, we suggest the ornamentation of spiracle peritremes and the types of body protuberances are useful characters for larval taxonomy within this group. Moreover, a few individuals were found possessing anomalous structures which are reminiscent of characters from related taxa. Finally, some brief observations are made on an unidentified parasite found inside some mature larvae of O. bauri.

Recovery modeling for OSB strand production from hollow bamboo culms

Current methods of reducing giant Moso bamboo (Phyllostachys pubescens Mazel) to elements for composite manufacture are often inefficient and waste valuable biomass. This study employed geometric modelling to analyze and optimize the recovery of strands for oriented strand board manufacture. Three geometric models for calculating the numbers of strands, their widths, and their distribution based on culm diameter, wall thickness, target strand thickness, and flitch size were developed to determine an optimum slicing configuration. Real strands were produced by a disk flaker at the model strand thickness of 0.65 mm. Optimum configuration for the maximum number of usable strands per culm was from splitting culms into quarters, tight stacking, and radial slicing through the culm wall, which produced 37% more ‘usable’ strands 10 mm to 30 mm in width, fewer fines, and fewer excessively wide strands. Proportions of real strands fell into three size classes: &lt; 10 mm, 10 mm to 30 mm, and &gt; 30 mm, and closely matched modelled predictions. A slightly bimodal strand width frequency distribution observed from stranding full rounds was reflected in the distribution of the model strands calculated from slicing a full round into 0.65 mm increments.

Size-frequency distributions of Joania cordata and Argyrotheca cuneata (Brachiopoda: Megathyrididae) from the Central Tyrrhenian Sea

Size-frequency distributions can support reliable inferences concerning population dynamics of brachiopods, but only a few data are available so far. In this study, length and width frequency distributions of dead specimens of the Recent brachiopods Joania cordata and Argyrotheca cuneata from the Marine Protected Area ‘Secche di Tor Paterno’, Central Tyrrhenian Sea, Italy (41°35′ N, 12°20′ E), are reported in order to add new data about size-frequency distributions of brachiopods. The studied specimens came from death assemblages in the coralligenous substrate, in the Posidonia oceanica meadows, and in the sand channels. The observed patterns vary from left-skewed (J. cordata) to right-skewed (A. cuneata), indicating respectively a low and high mortality of smaller individuals. Significant differences between the coralligenous substrate and the P. oceanica meadow were observed for both species, revealing a variation among different habitats. All length and width distributions are clearly polymodal, but the biological meaning of the peaks is difficult to interpret, as the two species seem to have a 2-year life span. A biometric analysis of shell sizes revealed that length and width are the most variable parameters during the growth of the animal.

Application of a Frequency Distribution Method for Determining Instars of the Beet Armyworm (Lepidoptera: Noctuidae) From Widths of Cast Head Capsules

Instar determination of field-collected insect larvae has generally been based on the analysis of head capsule width frequency distributions or bivariate plotting, but few studies have tested the validity of such methods. We used head capsules from exuviae of known instars of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), to determine the larval instars with the frequency distribution method and Dyar's rule. Head capsule widths of S. exigua ranged from 0.313 to 1.446 mm. The number of instars from the analytical method matched that from the observed data. Based on misclassification rules derived from nonlinear least square fitting of the head capsule width data, the theoretical misclassification rates ranged from 0.62 to 1.92%. Comparing the theoretical distribution to the observed data, the observational misclassification probabilities ranged from 1.18 to 3.03%. There were also 10 head capsules, eight third instars and two fourth instars, not classified into any of the known instars based on the theoretical distributions. Dyar's growth ratios of successive instars ranged from 1.41 to 1.65, and those based on the observed data and theoretical distribution were similar. Both approaches yielded a linear relationship between the natural logarithm of the mean head capsule width and the instar number, which indicates full representation of the larval instars. The results demonstrated that the frequency distribution-based method was robust, although we recommend caution when using such methods to classify head capsules into specific instar classes. Application of computer algorithms should also be accompanied by visual inspection to determine instars from the frequency distribution.

Age, growth, mortality and sex ratio of the inshore population of the edible crab, Cancer pagurus (Linnaeus 1758) in South Wales (UK)

Age, growth, and mortality of the edible crab, Cancer pagurus, were determined for the native population in South Wales (UK). Sampling was carried out on a monthly basis between February 2001 and September 2002. Carapace width ranged between 10.4 and 163 mm. Based on the carapace width frequency distribution, the Swansea and Gower population was composed mainly of males belonging to the first and second age-class (1 and 2), and of females belonging to the third and fourth age-class (3 and 4). Sex ratio was 1.126 ± 0.27 in favour of males. Carapace width frequency distributions and weight-at-age data were used to estimate the von Bertalanffy growth equation parameters. For the population as a whole, these were: L∞ = 199 mm, W∞ = 1179.56 g, K = 0.24 year−1, t0 = −0.1004 years. The overall carapace width–weight relationship was: W = 0.38(CW2.69). Analysis of covariance indicated a significant difference in the carapace width–weight relationship between males and females in the study area. Total mortality Z and natural mortality M rates for combined sexes were 1.245 year−1 and 0.567 year−1, respectively. The exploitation ratio E was estimated to be 54.43%.

PRECIOUS METALS IN SDSS QUASAR SPECTRA. I. TRACKING THE EVOLUTION OF STRONG, 1.5 &lt;z&lt; 4.5 C IV ABSORBERS WITH THOUSANDS OF SYSTEMS

We have vastly increased the CIV statistics at intermediate redshift by surveying the thousands of quasars in the Sloan Digital Sky Survey Data-Release 7. We visually verified over 16,000 CIV systems with 1.46 < z < 4.55---a sample size that renders Poisson error negligible. Detailed Monte Carlo simulations show we are approximately 50% complete down to rest equivalent widths W_r ~ 0.6 \AA. We analyzed the sample as a whole and in ten small redshift bins with approximately 1500 doublets each. The equivalent width frequency distributions f(W_r) were well modeled by an exponential, with little evolution in shape. In contrast with previous studies that modeled the frequency distribution as a single power law, the fitted exponential gives a finite mass density for the CIV ions. The co-moving line density dN_CIV/dX evolved smoothly with redshift, increasing by a factor of 2.37+/-0.09 from z = 4.55 to 1.96, then plateauing at dN_CIV/dX ~ 0.34 for z = 1.96 to 1.46. Comparing our SDSS sample with z < 1 (ultraviolet) and z > 5 (infrared) surveys, we see an approximately 10-fold increase in dN_CIV/dX over z ~ 6 --> 0, for W_r >= 0.6 \AA. This suggests a monotonic and significant increase in the enrichment of gas outside galaxies over the 12 Gyr lifetime of the universe.

PAC investigations of radiation damage annealing in 111In implanted ZnO

The structural and electronic environment about implanted radioactive 111In(→ 111Cd) probe atoms as a function of annealing temperature in a single crystal of ZnO(0 0 0 1) has been monitored on an atomic scale using perturbed angular correlation technique, a nuclear hyperfine method. This technique is based upon the hyperfine interaction of the nuclear electric quadrupole moment or magnetic moment of the probes, respectively, with the electric field gradient or magnetic hyperfine field arising from the extra-nuclear electronic charges and spin distributions. The probe atoms 111In were recoil-implanted at room temperature following heavy-ion nuclear reactions. The electric quadrupole interaction was measured at room temperature for as-implanted and annealed samples. The thermal annealing in ambient nitrogen up to 1000 °C showed a progressive reduction of disorder around the probe atom as evidenced via continual decrease in width of the distribution of quadrupole interaction frequencies. Present measurements suggested that annealing at 800 °C for 30 min in flowing nitrogen is enough to produce an optimum recovery of crystallinity. After annealing of radiation damage at 1000 °C we observed an axially symmetric electric field gradient which is characterized by the unique quadrupole interaction frequency of 30.6(3) MHz and a frequency distribution of width nearly zero. The observed electric field gradient was attributed to substitutional incorporation of probe atoms at cation-sites of ZnO. In contrast to annealing in ambient nitrogen at 1000 °C, air annealing of 111In implanted ZnO samples revealed change in local stoichiometry about probe atoms which is attributed to the internal oxidation of the indium probes. The measured electric field gradient and asymmetry parameter at cation-sites of ZnO have been compared with theoretical calculations using a simple point charge model.

Secondary production of Chasmagnathus granulatus (Crustacea; Decapoda) in a Ramsar Site from Argentina

Secondary production of Chasmagnathus granulatus was calculated at the Refugio de Vida Silvestre Bahía Samborombón, Argentina (36 degrees 16' S and 57 degrees 06' W). Sampling was conducted on nine occasions between March 2001 and February 2003, crabs were collected by hand, physico-chemical variables, granulometry and organic matter contents of the sediments were registered. Crabs were classified as male, female and undifferentiated, measured (total carapace width: CW) and weighed (wet and dry weight: DW at 60 degrees C, during 48 hours). A correlation analysis between CW and DW was made. Morphometric growth of C. granulatus was by the application of the power function (y = a x (b)), where the carapace width (CW) was used as an independent variable. Males, females and undifferentiated individuals were analysed separately as well as all together as a group. The data were fitted indicating a positive allometry (constant of allometry b > 3), the males showing the greatest allometric value. The individuals (n = 957 juveniles and adults) were separated in cohorts by the polymodal width-frequency distribution converted into normal curves. Three cohorts were found during the whole study period, and two cohorts coexisting in each sampling date. Ovigerous females were caught on December 2001, 2002 and February 2003. The size-frequency method was used to estimate the annual production. The major contribution to production was carried out by the mature individuals, in particular those with size between 25 and 30 mm, but on the other hand, only few individuals measuring from 10 to 20 mm were collected. The annual production of C. granulatus was estimated in 7.76 g.m(-2). The biomass (expressed as total dry weight) varied between 0.55 and 1.85 g.m(-2), with the greater values being registered during autumn and spring, and the lower values during summer.

Age structure and growth in cereal field populations of fungivorous beetle larvae, Atomaria spp. (Cryptophagidae; Col.), and the indirect effects of pesticides

Summary Effects of pesticides on populations of arthropods has been the subject of a vast number of field studies. Almost all of them analyse population effects in terms of changes in abundances although the study of other population features is common in population theory as well as in laboratory experiments. However, when estimating indirect non-toxic effects of pesticides on arthropods (arthropods affected by pesticide-mediated changes in their environment), realism in environmental conditions is crucial which is strongly in favour of field experimentation. The present study developed a method for the study of age structure and growth in field populations of fungivorous beetle larvae Atomaria spp., and tested it on field data for which abundances had previously been reported to respond negatively to herbicides and fungicides. The material comprised 2960 specimens originating from ‘D-vac’ suction sampling in a 2 × 2 factorial field plot experiment in winter wheat using samples from five sampling occasions and three sites. Treatments were designed to test the indirect non-toxic effects of herbicides (weed vegetation) and a fungicide, Tilt top , (non-target saprophytic fungi), respectively, on arthropods against untreated controls. Standard caput (head capsule) width measurements were used and subsequently, a standardized local scatter plot smoothing (S-PLUS procedure LOWESS with fixed specifications) was applied to caput width frequency distributions. Atomaria spp. caput width proved to be a quick, reliable and useful measure of larval population age structure and growth. Smoothing of caput width frequency distributions produced a similar four-peak pattern within each sampling occasion indicating the existence in Atomaria spp. of four larval instars, quite well distinguished by caput width measurements. However, while peaks (instars) I-II occurred at strikingly constant positions, the absolute position of peaks (instars) III-IV were less fixed. The strong numerical responses to both herbicide and fungicide treatment previously reported in larval Atomaria spp. were only in some cases accompanied by simultaneous changes in caput widths and here, the direction of effects changed over time. Thus, in the present limited sampling programme, some effects were observed, but they were not always similar. However, improved results and interpretations may well be expected when applying this method to field data (1) based on more frequent sampling and (2) balancing the dataset better by increasing the sample size from low-density populations in treated plots.

Statistical evidence for two major proteins in freeze‐fractured gastric parietal cell tubulovesicles and canaliculus

In a previous work, resting and acid-secreting rabbit gastric mucosa were freeze-fractured and shadowed at 45 degrees with Pt-C. The shadow widths of proteic particles of tubulovesicle and canaliculus membranes were measured and compared. It was concluded that the frequency distributions of widths are significantly different in resting and secreting membranes and that each distribution accounts for several subpopulations of homogeneous particles. In the present study, an attempt is made to describe the experimental distributions as a mixture of those of two major proteins, say A and B and their aggregates (AA, AB and BB). The modelling, although simple, gave a very satisfactory statistical fit between observed and computed distributions. The comparison of parameters calculated from histamine and ranitidine experimental data further improves the fits and finally, component A accounts for 69% of the particles. Most replica of A particles are heart-shaped and the median shadow widths are 6.1 and 6.8 nm in canaliculus and tubulovesicles respectively. The component B accounts for 31% of the particles. They mainly appear as small barrels and the median shadow widths are 8.8 and 10.3 nm in canaliculus and tubulovesicles respectively. According to calculated parameters and observed particle replica, the onset of secretion does not change the relative ratio of proteins but changes their shapes. Component A should be the (H+,K+)-ATPase whereas debate on the identity of B is wide open.