Shear and dewatering behaviour of densified gold tailings in a laboratory simulation of multi-layer deposition

2016 ◽  
Vol 53 (8) ◽  
pp. 1246-1257 ◽  
Author(s):  
Farzad Daliri ◽  
Paul Simms ◽  
Siva Sivathayalan
Keyword(s):  
Sampling Method ◽  
Drainage Water ◽  
Laboratory Simulation ◽  
Shear Behaviour ◽  
Thin Wall ◽  
Stress History ◽  
Bench Scale ◽  
Age Related ◽  
Layer Deposition ◽  
Gold Tailings

Tailings may undergo desiccation stress history under varied climatic and depositional parameters. While tailings substantially dewatered prior to deposition may experience desiccation under the greatest range of climatic variation, even conventionally deposited tailings may desiccate in arid climates at lower rates of rise. Bench-scale research has shown that the stress history imparted by desiccation substantially improves strength in gold tailings. The present study further investigates this phenomenon by simulating multi-layer deposition of high-density tailings using a modular drying box, 0.7 m by 1 m in plan. The box is instrumented for directly measuring evaporation, drainage, water content, vertical volume change, and matric suction. Additional measurements included total suction at the surface as well as observations of crack development. The dewatering behaviour conforms to that predicted by previously published generic modelling, specifically that the presence of partially desiccated tailings initially accelerates, but then decelerates dewatering of fresh tailings. The shear behaviour of samples obtained using buried tubes and by driving thin-wall tubes into the multi-layer simulation are compared with shear behaviour of samples from bench-scale experiments. Shear strength of samples from the multi-layer simulation is independent of the sampling method, and shows higher strength than the bench-scale samples. The higher strength may be due to the greater number of wet–dry cycles or other age-related processes.

110 ASSISTED CONCEPTION IN THE FISHING CAT BY LAPAROSCOPIC INTRATUBAL INSEMINATION

2014 ◽  
Vol 26 (1) ◽  
pp. 169
Author(s):  
C. E. Pope ◽  
M. C. Gómez ◽  
A. Cole ◽  
B. L. Dresser
Keyword(s):  
Embryo Transfer ◽  
Abdominal Cavity ◽  
Elective Caesarean Section ◽  
Sperm Concentration ◽  
Left Ovary ◽  
Laparoscopic Technique ◽  
Positive Pressure ◽  
Thin Wall ◽  
Age Related ◽  
The Right

Fishing cats (Prionailurus viverrinus) are small (6–15 kg) spotted cats from dispersed areas of Southeast Asia found mostly in wetland habitats. They are classified by the International Union for Conservation of Nature (IUCN) as endangered, with a decreasing population, due to habitat loss and degradation. Few studies have been done on applying assisted breeding techniques to the species, although the birth of a live kitten after IVF/embryo transfer (ET) has been reported (2006 Theriogenology 66, 1518–1524). Here, we describe the birth of a live fishing cat kitten using the technique of laparoscopic intratubal AI. A ten-year-old female who had served previously as an oocyte donor (5×) following gonadotropin treatment was administered a total of 5 IU of porcine FSH (Sioux Biochemical, Sioux City, Iowa) over 4 days (1×/day) followed by 10 IU of porcine LH on the fifth day. At approximately 28 h after LH treatment, the ovaries/oviduct were accessed by a laparoscopic technique comparable to that used for oviducal embryo transfer (ibid.). To deposit semen into the left oviduct, a 16-guage thin-wall trocar/needle was inserted into the abdominal cavity on the right side, approximately 1 cm lateral to the midline and approximately 2 to 3 cm below the umbilicus. A 14-cm open-end tom cat catheter was inserted into the 16-guage cannula (blunt) and the catheter tip was positioned underneath the fimbria overlaying the ovary. Then, a 50-mm length of 30-guage polytetrafluoroethylene (PTFE) thin-wall tubing containing approximately 30 μL of freshly collected semen was threaded through the catheter and the sample was expelled with positive pressure from a threaded-plunger 1-mL syringe. The left ovary contained 7 to 8 preovulatory (3–4 mm) follicles, 4 of which were manually ruptured immediately after deposition of semen with a 22-guage needle inserted through the 16-guage cannula. Then, with the 16-guage trocar/cannula in the same position (on the right side), the tip was redirected towards the right ovary and approximately 30 μL of semen was deposited underneath the fimbria as described above. The right ovary presented with 5 to 6 preovulatory (3–4 mm) follicles, 2 of which were punctured with the 22-guage needle after insemination. No ovulations were present on either ovary. The semen used for insemination was a fresh sample collected by electroejaculation from a 9-year-old male. The raw sperm concentration was 220 million mL–1, with 70% motility. The number of motile sperm deposited per oviduct was estimated to be approximately 4.6 million. The female was anesthetized 51 days later and radiography was done to determine her pregnancy status. A single fetus was present, so she was moved from an outdoor pen into a large indoor holding pen to allow for video-monitoring during the remainder of gestation. On Day 70, early signs of labour were observed and an elective Caesarean section was done approximately 4 h later. A live, healthy male kitten weighing 204 g was delivered. One year later, gonadotropin treatment/AI were repeated on the same pair. At approximately 30 h post-LH treatment, preovulatory follicles were present, but fewer than the previous treatment (5–6 total). Two fresh ovulation sites were seen on the left ovary. Pregnancy was not established. A reason for the failure was not apparent, unless it was age related.

Simulation of Temperature Field of Metal Thin Wall Parts during Laser Direct Deposition Rapid Prototyping

2011 ◽  
Vol 88-89 ◽  
pp. 42-45
Author(s):  
Wei Zhang ◽  
Shu Qin Shi
Keyword(s):  
Temperature Field ◽  
Element Model ◽  
Temperature Cycle ◽  
Thin Wall ◽  
Single Track ◽  
Heat Accumulation ◽  
Continuous Forming ◽  
Life And Death ◽  
Layer Deposition ◽  
Simulation And Experiment

The simulation of temperature field during laser direct metal deposition(DMD) were researched. The finite element model of single track cladding, multi-track overlapping and multi-layer deposition were established. The temperature field was simulated by ANSYS software basing on life-and-death element and cycle algorithm. Under different process parameters, the temperature and temperature gradient on the cross-section of sample were simulated during single- track scanning, multi-track overlapping and multi-layer deposition. Temperature cycle curves at different position were analyzed and were consistent with actually value. Both simulation and experiment showed that heat accumulation during continuous forming greatly affected the temperature of molten pool.

scholarly journals Elastoplastical Analysis of the Interface between Clay and Concrete Incorporating the Effect of the Normal Stress History

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Zhao Cheng ◽  
Zhao Chunfeng ◽  
Gong Hui
Keyword(s):  
Normal Stress ◽  
Load Transfer ◽  
Shear Behaviour ◽  
Model Parameters ◽  
Stress History ◽  
Hardening Parameter ◽  
Using Data ◽  
Energy Dissipated ◽  
Interaction Problem ◽  
Soil Interface

The behaviour of the soil-structure interface is crucial to the design of a pile foundation. Radial unloading occurs during the process of hole boring and concrete curing, which will affect the load transfer rule of the pile-soil interface. Through large shear tests on the interface between clay and concrete, it can be concluded that the normal stress history significantly influences the shear behaviour of the interface. The numerical simulation of the bored shaft-soil interaction problem requires proper modelling of the interface. By taking the energy accumulated on the interface as a hardening parameter and viewing the shearing process of the interface as the process of the energy dissipated to do work, considering the influence of the normal stress history on the shearing rigidity, a mechanical model of the interface between clay and concrete is proposed. The methods to define the model parameters are also introduced. The model is based on a legible mathematical theory, and all its parameters have definite physical meaning. The model was validated using data from a direct shear test; the validation results indicated that the model can reproduce and predict the mechanical behaviour of the interface between clay and concrete under an arbitrary stress history.

scholarly journals Evaluating the Performance of qVFM in Mapping the Visual Field of Simulated Observers With Eye Diseases

2021 ◽  
Vol 15 ◽  
Author(s):  
Pengjing Xu ◽  
Luis Andres Lesmes ◽  
Deyue Yu ◽  
Zhong-Lin Lu
Keyword(s):  
Visual Field ◽  
Sampling Method ◽  
Light Sensitivity ◽  
Age Related Macular Degeneration ◽  
Simulated Patients ◽  
Learning Framework ◽  
Age Related ◽  
Accuracy And Precision ◽  
Visual Field Maps ◽  
Real Patients

PurposeRecently, we developed a novel active learning framework, qVFM, to map visual functions in the visual field. The method has been implemented and validated in measuring light sensitivity and contrast sensitivity visual field maps (VFMs) of normal observers. In this study, we evaluated the performance of the qVFM method in mapping the light sensitivity VFM of simulated patients with peripheral scotoma, glaucoma, age-related macular degeneration (AMD), and cataract.MethodsFor each simulated patient, we sampled 100 locations (60 × 60 degrees) of the visual field and compared the performance of the qVFM method with a procedure that tests each location independently (the qYN method) in a cued Yes/No task. Two different switch modules, the distribution sampling method (DSM) and parameter delivering method (PDM), were implemented in the qVFM method. Simulated runs of 1,200 trials were used to compare the accuracy and precision of the qVFM-DSM, qVFM-PDM and qYN methods.ResultsThe qVFM method with both switch modules can provide accurate, precise, and efficient assessments of the light sensitivity VFM for the simulated patients, with the qVFM-PDM method better at detecting VFM deficits in the simulated glaucoma.ConclusionsThe qVFM method can be used to characterize residual vision of simulated ophthalmic patients. The study sets the stage for further investigation with real patients and potential translation of the method into clinical practice.

scholarly journals Hafnium (IV) oxide obtained by atomic layer deposition (ALD) technology promotes early osteogenesis via activation of Runx2-OPN-mir21A axis while inhibits osteoclasts activity

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
A. Seweryn ◽  
M. Alicka ◽  
A. Fal ◽  
K. Kornicka-Garbowska ◽  
K. Lawniczak-Jablonska ◽  
...  
Keyword(s):  
Healing Process ◽  
Atomic Layer ◽  
Deposition Process ◽  
Amorphous Layer ◽  
Biological Properties ◽  
Osteoporotic Bone ◽  
Metallic Biomaterials ◽  
Population Prevalence ◽  
Age Related ◽  
Layer Deposition

Abstract Background Due to increasing aging of population prevalence of age-related disorders including osteoporosis is rapidly growing. Due to health and economic impact of the disease, there is an urgent need to develop techniques supporting bone metabolism and bone regeneration after fracture. Due to imbalance between bone forming and bone resorbing cells, the healing process of osteoporotic bone is problematic and prolonged. Thus searching for agents able to restore the homeostasis between these cells is strongly desirable. Results In the present study, using ALD technology, we obtained homogeneous, amorphous layer of hafnium (IV) oxide (HfO2). Considering the specific growth rate (1.9Å/cycle) for the selected process at the temperature of 90 °C, we performed the 100 nm deposition process, which was confirmed by measuring film thickness using reflectometry. Then biological properties of the layer were investigated with pre-osteoblast (MC3T3), pre-osteoclasts (4B12) and macrophages (RAW 264.7) using immunofluorescence and RT-qPCR. We have shown, that HfO2 (i) enhance osteogenesis, (ii) reduce osteoclastogenesis (iii) do not elicit immune response and (iv) exert anti-inflammatory effects. Conclusion HfO2 layer can be applied to cover the surface of metallic biomaterials in order to enhance the healing process of osteoporotic bone fracture.

scholarly journals Pengaruh Terapi Musik Instrumental Terhadap Tekanan Darah Pada Lansia Hipertensi

2021 ◽  
Vol 14 (1) ◽  
pp. 27-34
Author(s):  
Nur Kholifah ◽  
Sutanta Sutanta
Keyword(s):  
Blood Pressure ◽  
Music Therapy ◽  
Elderly People ◽  
Sampling Method ◽  
The Elderly ◽  
Wilcoxon Test ◽  
P Value ◽  
Age Related ◽  
Lower Blood ◽  
Study Population

Background : Hypertensian can occur anyone, both men and women at any age. The elderly are at high risk of developing age-related degenerative diseases such as hypertension, one way to lower blood pressure in hypertensive sufferers using music therapy instrumental . The Aim :To Find out the effect of music therapy instrumental on blood pressure in elderly of hypertension at Panti Wredha Budhi Dharma Umbulharjo Yogyakarta. Methods :This research uses the pra ekperiment with One Group Pretest-Postest. The study population amounted to 52 elderly people , there are 30 samples elderly people by sampling methods using purposive sampling method. The research the method of data analysis uses Wilcoxon. Results : After performing music therapy instrumental showed blood pressure there are 28 people down (normal) and 2 fixed (high). The results ofthe Wilcoxon test, Z count value of -6.174 with p value 0,000 α = 0,05. Conclusion :There is a effect of music therapy instrumental on blood pressure in elderly of hypertension at Panti Wredha Budhi Dharma Umbulharjo Yogyakarta.

scholarly journals Relation Characteristics of Mother, ANC And Compliance of Maternity With Preeclampsia

2014 ◽  
Vol 2 (2) ◽  
pp. 216
Author(s):  
Elok Faiqoh ◽  
Lucia Hendrati
Keyword(s):  
Maternity Care ◽  
Sampling Method ◽  
Health Workers ◽  
Simple Random Sampling ◽  
Hypertensive Disorder ◽  
Sources Of Information ◽  
Chi Square ◽  
Age Related ◽  
Chi Square Test ◽  
History Of

ABSTRACTPreeclampsia is a hypertensive disorder in pregnancy which is accompanied by edema and proteinuria. This study aimed to analyze the characteristic of mothers, ANC visits and compliance maternity care of preeclampsia in dr. Mohamad Soewandhie Surabaya. This study is using case control with quantitative approach. Samples are 70 people who were taken by simple random sampling method with the distribution of samples 35 cases and 35 controls. The independent variables were age, history of hypertension, history of preeclampsia, primigravida, ANC and compliance of maternity care (provision of preeclampsia information, sources of information, advisory and compliance to suggestions). Data analysis was performed using Chi-Square test. The results showed that the variables are age-related (p = 0.014; OR 5.167), history of preeclampsia (p = 0.000), compliance of maternity care which includes the provision of preeclampsia information (p = 0.000), resources (p = 0.000; OR 0.045 ), provision of advice (p = 0.000; OR 0.015) and compliance of mother to advice (p = 0.000; OR 0.028). Unrelated variables is a history of hypertension (p = 0.198; OR 5.667), primigravida (p = 0.791; OR 0.755), and ANC (p = 0.733; OR 1.603). To reduce the occurrence of severe preeclampsia health workers are expected to be motivating mothers to provide relevant health education and knowledge relevant to the prevention of preeclampsia on the safe age to get pregnant and give birth, how to maintain their health with proper diet, adequate rest, regular medication given, examination timetable next ANC and other suggestions which is may help prevent or reduce the risk of preeclampsia.Keywords: preeclampsia, age, history of preeclampsia, compliance

scholarly journals Relation Characteristics of Mother, ANC And Compliance of Maternity With Preeclampsia

2014 ◽  
Vol 2 (2) ◽  
pp. 216
Author(s):  
Elok Faiqoh ◽  
Lucia Hendrati
Keyword(s):  
Maternity Care ◽  
Sampling Method ◽  
Health Workers ◽  
Simple Random Sampling ◽  
Hypertensive Disorder ◽  
Sources Of Information ◽  
Chi Square ◽  
Age Related ◽  
Chi Square Test ◽  
History Of

ABSTRACTPreeclampsia is a hypertensive disorder in pregnancy which is accompanied by edema and proteinuria. This study aimed to analyze the characteristic of mothers, ANC visits and compliance maternity care of preeclampsia in dr. Mohamad Soewandhie Surabaya. This study is using case control with quantitative approach. Samples are 70 people who were taken by simple random sampling method with the distribution of samples 35 cases and 35 controls. The independent variables were age, history of hypertension, history of preeclampsia, primigravida, ANC and compliance of maternity care (provision of preeclampsia information, sources of information, advisory and compliance to suggestions). Data analysis was performed using Chi-Square test. The results showed that the variables are age-related (p = 0.014; OR 5.167), history of preeclampsia (p = 0.000), compliance of maternity care which includes the provision of preeclampsia information (p = 0.000), resources (p = 0.000; OR 0.045 ), provision of advice (p = 0.000; OR 0.015) and compliance of mother to advice (p = 0.000; OR 0.028). Unrelated variables is a history of hypertension (p = 0.198; OR 5.667), primigravida (p = 0.791; OR 0.755), and ANC (p = 0.733; OR 1.603). To reduce the occurrence of severe preeclampsia health workers are expected to be motivating mothers to provide relevant health education and knowledge relevant to the prevention of preeclampsia on the safe age to get pregnant and give birth, how to maintain their health with proper diet, adequate rest, regular medication given, examination timetable next ANC and other suggestions which is may help prevent or reduce the risk of preeclampsia.Keywords: preeclampsia, age, history of preeclampsia, compliance

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