Low or high aspiration vacuum pressure to yield oocytes for poor responder in oocyte pick-up procedure

2013 ◽  
Vol 100 (3) ◽  
pp. S475
Author(s):  
S. Guven ◽  
C. Kart ◽  
M. Unsal ◽  
E. Odaci ◽  
E. Yulug ◽  
...  
Keyword(s):  
Poor Responder ◽  
Vacuum Pressure ◽  
High Aspiration

Method and results of experimental researches of modes of work of the adaptive milking equipment on the basis of the portion meter of the weight type

2020 ◽  
pp. 140-146
Author(s):  
I. A. Afanasiev ◽  
V. V. Tkach
Keyword(s):  
Regression Analysis ◽  
Vacuum Pressure ◽  
Limit Values ◽  
Operating Modes ◽  
Machine Milking ◽  
Milk Output ◽  
Mode Of Operation ◽  
Milking Machine ◽  
Experimental Researches

Annotation Purpose. Improving the efficiency of machine milking due to the improvement of milking equipment on the basis of the portion meter of the weight type. Methods. Studies have been conducted on the basis of the planned experiment. The data obtained were processed using the methods of regression analysis. Results. The technique of laboratory researches is developed, a prototype of a membrane regulator of vacuum is made and experimental researches of operating modes of the adaptive milking equipment on the basis of the portion meter of the weight type. According to the results of the research, the dependence between the parameters and the mode of operation of the membrane vacuum regulator was obtained. Conclusions. The dependence is obtained, between the vacuum pressure in the milk collection chamber of the collector, milk expense, the diameters of the milk pipe and the diameters of a throttle opening. The limit values of the intensity of milk output (0.2 m3/s) at which there is a critical drop in the working vacuum pressure in the milk collection chamber of the collector and the corresponding choke parameters (diameter of the throttle opening 0,001 m) are defined. This eliminates this negative phenomenon. Keywords: adaptive milking equipment, milking machine, machine milking, milk expense.

Optimization of the operational parameters of a picking-type pneumatic planter using response surface methodology

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
SK PATEL ◽  
JB BHIMANI ◽  
P GUPTA ◽  
BK YADUVANSHI
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Important Variable ◽  
Vacuum Pressure ◽  
Forward Speed ◽  
Operational Parameters ◽  
Seed Spacing ◽  
Lady’S Finger ◽  
Multiple Regression Technique ◽  
Seed Metering Device

Singulation of seeds has been investigated extensively by researchers all over the world and a large number of precision seeding systems with design variations have been developed for different crops. A picking type metering mechanism was developed at CAET, AAU, Godhra, Gujarat, India. The performance of the picking type seed-metering device of a pneumatic planter was investigated under laboratory conditions to optimize the operating parameters for lady's finger seed. The picking of single seed the three operational parameters i.e. hole diameters for the nozzle: 1.0, 1.5, 2.5 and 3.0 mm; forward speed: 0.37, 0.56, 0.83, 1.11 and 1.30 m/s and vacuum pressure: 19.33, 39.32, 43.98, 58.64 and 68.63 kPa were selected for the study. The metering system of the planter was set to place the seed to seed spacing at 300 mm. The response surface methodology (RSM) technique was used to optimize the operational parameters of a precision planter. For optimizing the forward speed, vacuum pressure and nozzle size for developed machine was evaluated by examining the miss index, multiple index, quality of feed index and precision. The data obtained in the experiments were used to develop functions in polynomial form using multiple regression technique. The optimum value was found to be around 0.96 m/s, 36.25 kPa and 2.0 mm of forward speed, vacuum pressure and the holes diameter of nozzle, respectively. The most important variable that governs planting phenomenon is the combination of hole diameter of nozzle and vacuum pressure accounts 89.18 per cent.

Can serum estradiol levels on the fourth day of IVF/ICSI cycle predict outcome in poor responder women?

2015 ◽  
Vol 61 (4) ◽  
pp. 233-237 ◽  
Author(s):  
Serkan Kahyaoglu ◽  
Omer H. Yumusak ◽  
A. Seval Ozgu-Erdinc ◽  
Saynur Yilmaz ◽  
Inci Kahyaoglu ◽  
...  
Keyword(s):  
Poor Responder ◽  
Serum Estradiol ◽  
Icsi Cycle ◽  
Estradiol Levels

scholarly journals Numerical Simulation of the Water Vapor Separation of a Moisture-Selective Hollow-Fiber Membrane for the Application in Wood Drying Processes

Membranes ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 593
Author(s):  
Nasim Alikhani ◽  
Douglas W. Bousfield ◽  
Jinwu Wang ◽  
Ling Li ◽  
Mehdi Tajvidi
Keyword(s):  
Water Vapor ◽  
Constant Temperature ◽  
Hollow Fiber ◽  
Hollow Fiber Membrane ◽  
Vacuum Pressure ◽  
Vapor Concentration ◽  
Water Vapor Concentration ◽  
Fiber Membrane ◽  
Wood Drying ◽  
Air Velocity

In this study, a simplified two-dimensional axisymmetric finite element analysis (FEA) model was developed, using COMSOL Multiphysics® software, to simulate the water vapor separation in a moisture-selective hollow-fiber membrane for the application of air dehumidification in wood drying processes. The membrane material was dense polydimethylsiloxane (PDMS). A single hollow fiber membrane was modelled. The mass and momentum transfer equations were simultaneously solved to compute the water vapor concentration profile in the single hollow fiber membrane. A water vapor removal experiment was conducted by using a lab-scale PDMS hollow fiber membrane module operated at constant temperature of 35 °C. Three operation parameters of air flow rate, vacuum pressure, and initial relative humidity (RH) were set at different levels. The final RH of dehydrated air was collected and converted to water vapor concentration to validate simulated results. The simulated results were fairly consistent with the experimental data. Both experimental and simulated results revealed that the water vapor removal efficiency of the membrane system was affected by air velocity and vacuum pressure. A high water vapor removal performance was achieved at a slow air velocity and high vacuum pressure. Subsequently, the correlation of Sherwood (Sh)–Reynolds (Re)–Schmidt (Sc) numbers of the PDMS membrane was established using the validated model, which is applicable at a constant temperature of 35 °C and vacuum pressure of 77.9 kPa. This study delivers an insight into the mass transport in the moisture-selective dense PDMS hollow fiber membrane-based air dehumidification process, with the aims of providing a useful reference to the scale-up design, process optimization and module development using hollow fiber membrane materials.

scholarly journals Natural Cycle Results in Lower Implantation Failure than Ovarian Stimulation in Advanced-Age Poor Responders Undergoing IVF: Fertility Outcomes from 585 Patients

2021 ◽  
Author(s):  
Maria Paola De Marco ◽  
Giulia Montanari ◽  
Ilary Ruscito ◽  
Annalise Giallonardo ◽  
Filippo Maria Ubaldi ◽  
...  
Keyword(s):  
Pregnancy Rate ◽  
Ovarian Stimulation ◽  
Embryo Implantation ◽  
Implantation Rate ◽  
Poor Responder ◽  
Advanced Age ◽  
Poor Responders ◽  
Natural Cycle ◽  
Significant Difference ◽  
Over 40 Years

AbstractTo compare pregnancy rate and implantation rate in poor responder women, aged over 40 years, who underwent natural cycle versus conventional ovarian stimulation. This is a retrospective single-center cohort study conducted at the GENERA IVF program, Rome, Italy, between September 2012 and December 2018, including only poor responder patients, according to Bologna criteria, of advanced age, who underwent IVF treatment through Natural Cycle or conventional ovarian stimulation. Between September 2012 and December 2018, 585 patients were included within the study. Two hundred thirty patients underwent natural cycle and 355 underwent conventional ovarian stimulation. In natural cycle group, both pregnancy rate per cycle (6.25 vs 12.89%, respectively, p = 0.0001) and pregnancy rate per patient101 with at least one embryo-transfer (18.85 vs 28.11% respectively, p = 0.025) resulted significant reduced. Pregnancy rate per patient managed with conventional ovarian stimulation resulted not significantly different compared with natural cycle (19.72 vs 15.65% respectively, p = 0.228), but embryo implantation rate was significantly higher in patients who underwent natural cycle rather than patient subjected to conventional ovarian stimulation (13 vs 8.28% respectively, p = 0.0468). No significant difference could be detected among the two groups in terms of abortion rate (p = 0.2915) or live birth pregnancy (p = 0.2281). Natural cycle seems to be a valid treatment in patients over 40 years and with a low ovarian reserve, as an alternative to conventional ovarian stimulation.

scholarly journals Vacuum Venting Enhances the Replication of Nano/Microfeatures in Micro-Injection Molding Process

2016 ◽  
Vol 4 (2) ◽  
Author(s):  
Seong Ying Choi ◽  
Nan Zhang ◽  
J. P. Toner ◽  
G. Dunne ◽  
Michael D. Gilchrist
Keyword(s):  
Injection Molding ◽  
Quantitative Study ◽  
Vacuum Pressure ◽  
Injection Molding Process ◽  
Anodized Aluminum ◽  
Molding Process ◽  
Micro Injection Molding ◽  
Sample Shape ◽  
Final Sample ◽  
Qualitative And Quantitative Study

Vacuum venting is a method proposed to improve feature replication in microparts that are fabricated using micro-injection molding (MIM). A qualitative and quantitative study has been carried out to investigate the effect of vacuum venting on the nano/microfeature replication in MIM. Anodized aluminum oxide (AAO) containing nanofeatures and a bulk metallic glass (BMG) tool mold containing microfeatures were used as mold inserts. The effect of vacuum pressure at constant vacuum time, and of vacuum time at constant vacuum pressure on the replication of these features is investigated. It is found that vacuum venting qualitatively enhances the nanoscale feature definition as well as increases the area of feature replication. In the quantitative study, higher aspect ratio (AR) features can be replicated more effectively using vacuum venting. Increasing both vacuum pressure and vacuum time are found to improve the depth of replication, with the vacuum pressure having more influence. Feature orientation and final sample shape could affect the absolute depth of replication of a particular feature within the sample.

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