Behavioural features of Bursaphelenchus xylophilus in the mating process

Nematology ◽  
2014 ◽  
Vol 16 (8) ◽  
pp. 895-902 ◽  
Author(s):  
Bao-Jun Liu ◽  
Jia-Fu Hu ◽  
Zhen-Yu Liu ◽  
Liang Xu ◽  
Quan Lu ◽  
...  
Keyword(s):  
Sex Pheromone ◽  
Mating Behaviour ◽  
Bursaphelenchus Xylophilus ◽  
Pine Wood Nematode ◽  
Sexual Competition ◽  
Repeated Observations ◽  
Long Time ◽  
The Mean ◽  
Mating Choice ◽  
Short Time

The pine wood nematode (PWN), Bursaphelenchus xylophilus, is able to produce hundreds of thousands of offspring in a short time. Its mating behaviour might play a basic role in this marked fecundity. We investigated the features of the mating behaviour of B. xylophilus using long-time microscope video and repeated observations. The mating behaviour of B. xylophilus could be separated into a series of sequential sub-behaviours, including cruising, approaching, encountering, touching, hooping, locating, attaching, ejaculating, separating, quiescence and roaming. Overall, the process of mating behaviour could be divided into four different phases, searching, contacting, copulating and lingering; the mean times for these different phases varied significantly with 21.8 ± 2.0 min, 28.0 ± 1.9 min, 23.6 ± 0.7 min and 7.2 ± 0.5 min for each of the four phases, respectively. Attraction between the sexes was observed, indicating that sex pheromone(s) might be involved in mating behaviour of B. xylophilus. In addition, when one female was placed with three males, male-male competition was observed, which might be caused by mating-choice pressure from the female. Intra-sexual competition of females was also occasionally observed.

scholarly journals Primary Intraventricular Hemorrhage in Pediatric Patients: Causes, Characteristics, and Outcomes

2019 ◽  
Author(s):  
Rui Guo ◽  
Chaofeng Fan ◽  
Ruiqi Chen ◽  
Zhiyuan Yu ◽  
Rui Tian ◽  
...  
Keyword(s):  
Intraventricular Hemorrhage ◽  
Arteriovenous Malformations ◽  
Pediatric Patients ◽  
Pediatric Population ◽  
Unfavorable Outcome ◽  
Rare Type ◽  
Long Time ◽  
The Mean ◽  
Short Time

Abstract Background: Primary intraventricular hemorrhage is a rare type of stroke and little is known its causes, characteristics and outcomes in children. Methods: We retrospectively analyzed the clinical characteristics of patients aged one month to 21 years during seven consecutive years with primary intraventricular hemorrhage. Primary intraventricular hemorrhage was defined as bleeding confined to the ventricular system without parenchymal or subarachnoid hemorrhage involved. Results: Of the included eighteen patients, 55.6% were female, and the mean age was 13.8 ± 6.0 years. The most common symptoms on presentation were headache (77.8%) and vomiting (33.3%). Fifteen patients (83.3%) were diagnosed with known etiologies, including arteriovenous malformations (66.7%), Moyamoya disease (11.1%), and aneurysms (5.6%). Idiopathic PIVH was diagnosed in only 3 patients (16.7%). Fifteen patients (83.3%) underwent surgical intervention, and 3 patients (16.7%) received conservative treatment. Four patients (28.6%) had an unfavorable outcome at discharge and unfavorable was observed in 3 patients (16.7%) at the 3-month follow-up. Higher Graeb score was associated with an unfavorable outcome both in short-time and long-time follow-up. Conclusions: Most primary intraventricular hemorrhage patients were diagnosed with arteriovenous malformations in the pediatric population. Specific surgical treatment of underlying etiologies should be required to increase clinical improvement. The children with higher Graeb score at admission tended to have poor early and late outcome. Keywords: Primary intraventricular hemorrhage; pediatric; surgery; vascular disorders.

Intracrystalline Transport Barriers Affecting the Self-Diffusion of CH4 in Zeolites |Na12|-A and |Na12-xKx|-A

2018 ◽  
Author(s):  
Niklas Hedin ◽  
Przemyslaw Rzepka ◽  
Alma Jasso-Salcedo ◽  
Tamara L. Church ◽  
Diana Bernin
Keyword(s):  
Close Contact ◽  
Mean Square Displacement ◽  
Diffusion Time ◽  
Mean Square ◽  
Zeolite A ◽  
Self Diffusion ◽  
Transport Barriers ◽  
Long Time ◽  
The Mean ◽  
Short Time

<p>Removing carbon dioxide is important for the upgrading of biogas or natural gas into compressed or liquefied methane, and adsorption-driven separation of CO<sub>2</sub> could be further advanced by developing for example new adsorbents. Zeolite adsorbents can select CO<sub>2</sub> over CH<sub>4</sub>, and we here confirmed that the adsorption of CH<sub>4</sub> on zeolite |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A was significantly lower for samples with a high K<sup>+</sup> content, i.e. <i>x</i> > 2. Nevertheless, these samples adsorb CH<sub>4</sub> after long equilibration times as determined with <sup>1</sup>H NMR experiments. To assess further the intracrystalline diffusion of CH<sub>4</sub> in these zeolites, pulsed-field gradient NMR experiments were performed. In large crystals of zeolites |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A, the long-time diffusion coefficients of CH<sub>4</sub> did not vary with <i>x</i>, and the mean square displacement was about 1.5 mm irrespective of the diffusion time. Also for zeolite |Na<sub>12</sub>|-A samples of three different particle sizes (~0.44, ~2.9, ~10.6 mm), the mean-square displacement of CH<sub>4</sub> was 1.5 mm and largely independent of the diffusion time. This similarity provided further evidence for an intracrystalline diffusion restriction for CH<sub>4</sub> within the medium- and large-sized zeolite A crystals, and possibly of clustering and close contact among the small zeolite A crystals. The long-time diffusion coefficient of adsorbed CH<sub>4</sub> was (at 1 atm and 298 K) about 1 ´ 10<sup>–10</sup> m<sup>2</sup>/s irrespective of the size of the zeolite particle or the studied content of K<sup>+</sup> in zeolites |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A and |Na<sub>12</sub>|-A. The <i>T</i><sub>1</sub><i> </i>relaxation time for adsorbed CH<sub>4</sub> on zeolites |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A with <i>x</i> > 2 was smaller than for those with <i>x</i> < 2, indicating that the short-time diffusion of CH<sub>4</sub> was hindered.</p>

Intracrystalline Transport Barriers Affecting the Self-Diffusion of CH4 in Zeolites |Na12|-A and |Na12-xKx|-A

2018 ◽  
Author(s):  
Niklas Hedin ◽  
Przemyslaw Rzepka ◽  
Alma Jasso-Salcedo ◽  
Tamara L. Church ◽  
Diana Bernin
Keyword(s):  
Close Contact ◽  
Mean Square Displacement ◽  
Diffusion Time ◽  
Mean Square ◽  
Zeolite A ◽  
Self Diffusion ◽  
Transport Barriers ◽  
Long Time ◽  
The Mean ◽  
Short Time

<p>Removing carbon dioxide is important for the upgrading of biogas or natural gas into compressed or liquefied methane, and adsorption-driven separation of CO<sub>2</sub> could be further advanced by developing for example new adsorbents. Zeolite adsorbents can select CO<sub>2</sub> over CH<sub>4</sub>, and we here confirmed that the adsorption of CH<sub>4</sub> on zeolite |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A was significantly lower for samples with a high K<sup>+</sup> content, i.e. <i>x</i> > 2. Nevertheless, these samples adsorb CH<sub>4</sub> after long equilibration times as determined with <sup>1</sup>H NMR experiments. To assess further the intracrystalline diffusion of CH<sub>4</sub> in these zeolites, pulsed-field gradient NMR experiments were performed. In large crystals of zeolites |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A, the long-time diffusion coefficients of CH<sub>4</sub> did not vary with <i>x</i>, and the mean square displacement was about 1.5 mm irrespective of the diffusion time. Also for zeolite |Na<sub>12</sub>|-A samples of three different particle sizes (~0.44, ~2.9, ~10.6 mm), the mean-square displacement of CH<sub>4</sub> was 1.5 mm and largely independent of the diffusion time. This similarity provided further evidence for an intracrystalline diffusion restriction for CH<sub>4</sub> within the medium- and large-sized zeolite A crystals, and possibly of clustering and close contact among the small zeolite A crystals. The long-time diffusion coefficient of adsorbed CH<sub>4</sub> was (at 1 atm and 298 K) about 1 ´ 10<sup>–10</sup> m<sup>2</sup>/s irrespective of the size of the zeolite particle or the studied content of K<sup>+</sup> in zeolites |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A and |Na<sub>12</sub>|-A. The <i>T</i><sub>1</sub><i> </i>relaxation time for adsorbed CH<sub>4</sub> on zeolites |Na<sub>12-<i>x</i></sub>K<i><sub>x</sub></i>|-A with <i>x</i> > 2 was smaller than for those with <i>x</i> < 2, indicating that the short-time diffusion of CH<sub>4</sub> was hindered.</p>

scholarly journals VI. Experiments upon the heart of the dog with reference to the maximum volume of blood sent out by the left ventricle in a single beat and the influence of variations in venous pressure, arterial pressure, and pulse-rate upon the work done by the heart

1884 ◽  
Vol 175 ◽  
pp. 139-160 ◽  
Keyword(s):  
Venous Pressure ◽  
Uncertain Data ◽  
Mean Velocity ◽  
Long Time ◽  
Cause Of Failure ◽  
The Mean ◽  
The Right ◽  
The University ◽  
Short Time ◽  
Work Done

The most important factor to be determined before calculating the work done by the heart is the quantity of blood forced from the ventricles at each systole. Most of the efforts to determine this quantity have been based either upon faulty observations upon the dead heart, or upon the uncertain data obtained by estimating the mean velocity of the stream of blood in the aorta. Professor Martin accordingly suggested to us that we should attempt to measure it directly on the isolated Dog’s heart. The work thus undertaken was carried on during the greater part of the university session, 1881-82, and the results obtained are given in the following pages. The method of isolating the heart was essentially that described in Professor Martin’s paper (Phil. Trans., 1883, p. 663). In the course of this work many unexpected difficulties arose, necessitating changes in the apparatus and the method of operating, and preventing us for a long time from obtaining any successful results. In our experiments it was necessary not only that the heart should live and beat, but that it should be in the best possible physiological condition, and any marked pulmonary œdema made an experiment nearly valueless. This most frequent cause of failure was mainly owing to the fact that, on account of the large quantity of blood required for an experiment, we were obliged to use Calf’s blood obtained from the butcher; very often this blood, as Professor Martin states in his paper, will bring about œdema of the lungs in a short time; large quantities of exuded serum pour out of the tracheal cannula, the air-passages in the lungs become choked up with liquid, and the circulation from the right to the left side of the heart is greatly impeded. We have succeeded, however, in making a considerable number of experiments in which all the conditions were favourable, the œdema of the lungs not occurring to any marked extent until after many observations had been made.

scholarly journals Assessing the probability of freedom from pine wood nematode based on 19 years of surveys

NeoBiota ◽  
2020 ◽  
Vol 58 ◽  
pp. 75-106
Author(s):  
Salla Hannunen ◽  
Juha Tuomola
Keyword(s):  
Early Detection ◽  
Quantitative Estimate ◽  
Bursaphelenchus Xylophilus ◽  
Pine Wood Nematode ◽  
Pine Wood ◽  
Quarantine Pest ◽  
System Sensitivity ◽  
The Mean ◽  
The One ◽  
Mean Time

Many quarantine pests, such as the pine wood nematode (PWN, Bursaphelenchus xylophilus), are surveyed annually in all EU countries. Although a lot of resources are spent in the surveys, the confidence in pest freedom achieved with them is not commonly analysed. We assessed the probability that Finland is free from PWN, based on the surveys done in 2000–2018. We used the methods employed in the risk-based estimate of system sensitivity tool (RiBESS), which has recently been recommended for quarantine pest applications. We considered two scenarios: 1) the surveys aimed to justify phytosanitary import requirements and to facilitate exports and 2) the surveys aimed to detect invasions early to enable eradication of outbreaks. These differed only in the pest prevalence that the surveys were expected to detect. The surveys appeared to support the assumption that PWN is not present in Finland, but they did not seem extensive enough to ensure early detection of invasions. The sensitivity of the import-export surveys was greater than 0.6 in 13 years, whereas that of the early detection surveys was always below 0.25. The probability of freedom achieved in 2018 following 19 years of surveys increased asymptotically with the mean time between invasions. For the import-export surveys, this probability was at least 0.95 unless the mean time between invasions was less than 13 years. For the early detection surveys, the probability of freedom was less than 0.73 unless the mean time between invasions was 63 years or more. The results were rather robust with respect to the parameters for which exact information was lacking. To improve the assessment, a quantitative estimate of the probability of PWN invasion to Finland and a thorough assessment of the maximum area of an eradicable infestation would be needed. To gain an understanding about the true impact of quarantine pest surveys on biosecurity, more assessments, like the one presented in this paper, are needed.

Short-Time Tests for Long-Time Endurance

1923 ◽  
Vol 128 (4) ◽  
pp. 264-264
Author(s):  
J. W. Harsch
Keyword(s):  
Long Time ◽  
Short Time

Effect of Vial shaking on Loading Time of Epirubicin into Drug-Eluting Bead

2015 ◽  
Vol 5 (3) ◽  
Author(s):  
Kenji Ikeda ◽  
Yusuke Kawamura ◽  
Masahiro Kobayashi ◽  
Taito Fukushima ◽  
Yushi Sorin ◽  
...  
Keyword(s):  
Antitumor Agent ◽  
Loading Rates ◽  
Vortex Mixer ◽  
Long Time ◽  
Group A ◽  
Drug Eluting ◽  
Large Hepatocellular Carcinoma ◽  
Group B ◽  
Time Required ◽  
Short Time

Background: Although DC Bead has been useful in treatment of multiple and large hepatocellular carcinoma, loading time of doxorubicin into the DC Bead takes a long time of 30-120 minutes. Epirubicin is also used as an antitumor agent together with DC Bead, but its loading efficiency was not sufficiently elucidated. Methods: To shorten loading time of epirubicin into DC Bead (100-300µm, 300-500µm, 500-700µm), we examined the following three methods after mixing the drug: (a) let stand in room temperature, (b) agitated for 30 seconds with Vortex mixer, and (c) sonicated for 30 seconds with ultrasonic cleaner. After loading of epirubicin by each method, supernatant concentration for epirubicin was assayed at 5, 10, 30, 60, and 120 minutes. Results: Epirubicin loading rates for small bead (100-300µm) at 5 minutes were 82.9 % in group a, 93.8% in group b, and 79.9 % in group c. Similarly, medium bead (300-500µm), 40.1% in group a, 65.7% in group b and 45.5% in group c, respectively. In large-sized bead (500-700µm), loaded rates of epirubicin were 38.8% in group a, 59.0% in group b and 48.0% in group c. Agitation of mixture of epirubicin and DC Bead with Vortex mixer significantly shortened the loading time, but sonication did not affect the time required. Microscopic examination did not lead to any morphological change of microspheres in all the methods. Conclusions: Short time of agitation with Vortex mixer reduced the necessary time for loading of epirubicin in every standard of DC Bead.

Robust Test Method of TSOP PEMs for Space Application

2019 ◽  
Author(s):  
Yasunobu Iwai ◽  
Koichi Shinozaki ◽  
Daiki Tanaka
Keyword(s):  
Evaluation Method ◽  
Low Cost ◽  
Reliability Evaluation ◽  
Test Method ◽  
Thermal Shock Test ◽  
Space Application ◽  
Space Applications ◽  
Limit Test ◽  
Long Time ◽  
Short Time

Abstract Compared with space parts, consumer parts are highly functional, low cost, compact and lightweight. Therefore, their increased usage in space applications is expected. Prior testing and evaluation on space applicability are necessary because consumer parts do not have quality guarantees for space application [1]. However, in the conventional reliability evaluation method, the test takes a long time, and the problem is that the robustness of the target sample can’t be evaluated in a short time. In this report, we apply to the latest TSOP PEM (Thin Small Outline Package Plastic Encapsulated Microcircuit) an evaluation method that combines preconditioning and HALT (Highly Accelerated Limit Test), which is a test method that causes failures in a short time under very severe environmental conditions. We show that this method can evaluate the robustness of TSOP PEMs including solder connections in a short time. In addition, the validity of this evaluation method for TSOP PEM is shown by comparing with the evaluation results of thermal shock test and life test, which are conventional reliability evaluation methods.

The Spread of Pollutants from Harbour Sludge Depots

1984 ◽  
Vol 16 (3-4) ◽  
pp. 623-633
Author(s):  
M Loxham ◽  
F Weststrate
Keyword(s):  
Time Scales ◽  
Molecular Diffusion ◽  
Near Field ◽  
Parameter Analysis ◽  
Migration Patterns ◽  
Long Time ◽  
Dilution Effects ◽  
Short Time ◽  
Harbour Sludge

It is generally agreed that both the landfill option, or the civil techniques option for the final disposal of contaminated harbour sludge involves the isolation of the sludge from the environment. For short time scales, engineered barriers such as a bentonite screen, plastic sheets, pumping strategies etc. can be used. However for long time scales the effectiveness of such measures cannot be counted upon. It is thus necessary to be able to predict the long term environmenttal spread of contaminants from a mature landfill. A model is presented that considers diffusion and adsorption in the landfill site and convection and adsorption in the underlaying aquifer. From a parameter analysis starting form practical values it is shown that the adsorption behaviour and the molecular diffusion coefficient of the sludge, are the key parameters involved in the near field. The dilution effects of the far field migration patterns are also illustrated.

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