An Investigation into the Potential Use of Calcium Carbonate Nanoparticles in Mine Backfill

2018 ◽  
Vol 916 ◽  
pp. 184-189
Author(s):  
Mohammed A. Hefni ◽  
Ferri P. Hassani ◽  
Mehrdad F. Kermani
Keyword(s):  
Calcium Carbonate ◽  
Phase I ◽  
Phase Ii ◽  
Particle Dispersion ◽  
Silica Sand ◽  
Binding Agent ◽  
Dispersion Phase ◽  
Mine Backfill ◽  
Before And After ◽  
Potential Use

This study is part of large and ongoing investigation into the potential use of calcium carbonate nanoparticles (NCaCO3) to improve the mechanical and physical properties of mine backfill. The investigation was conducted in two phases. In phase I, gold tailings were used to prepare backfill sample using Portland cement (PC) as the binding agent under various NCaCO3 and superplasticizer (SP) dosages. In phase II, fine silica sand was used to minimize the reactive nature of tailings, which can adversely affect uniaxial compressive strength (UCS). Samples in this phase were prepared under various NCaCO3 dosages using slag:PC weight ratios of 80:20 as the binding agent. Select samples from phase II were subjected to Mercury Intrusion Porosimetry (MIP) to compare microstructural properties before and after addition of NCaCO3. Phase I results showed that the UCS of samples containing NCaCO3 was low, even when SP was used to improve particle dispersion. Phase II samples exhibited up to 9.5% higher UCS after 28 days of curing at a NCaCO3 dosage of 6% by weight of binder. MIP results showed that samples containing NCaCO3 were less porous than the corresponding controlled silica sand backfill samples, which in turn influenced the UCS results.

scholarly journals Involvement of NO in Antinociception of NSAIDS in Murine Formalin Hind Paw Assay

Drug Research ◽  
2020 ◽  
Vol 70 (04) ◽  
pp. 145-150 ◽  
Author(s):  
Viviana Noriega ◽  
Hugo F. Miranda ◽  
Juan Carlos Prieto ◽  
Ramón Sotomayor-Zárate ◽  
Fernando Sierralta
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Dose Response ◽  
Rank Order ◽  
Linear Regression Analysis ◽  
Second Phase ◽  
Response Curves ◽  
Before And After ◽  
Two Phases ◽  
Phase Phase

AbstractThere are different animal models to evaluate pain among them the formalin hind paw assay which is widely used since some of its events appear to be similar to the clinical pain of humans. The assay in which a dilute solution of formalin is injected into the dorsal hindpaw of a murine produces two ‘phases’ of pain behavior separated by a inactive period. The early phase (Phase I) is probably due to direct activation of nociceptors and the second phase (Phase II) is due to ongoing inflammatory input and central sensitization. Mice were used to determine the potency antinociceptive of piroxicam (1,3,10,and 30 mg/kg), parecoxib (0.3, 1,3,10 and 30 mg/kg), dexketoprofen (3,10,30 and 100 mg/kg) and ketoprofen (3,10,30 and 100 mg/kg). Dose-response for each NSAIDs were created before and after 5 mg/kg of L-NAME i.p. or 5 mg/kg i.p. of 7-nitroindazole. A least-squares linear regression analysis of the log dose–response curves allowed the calculation of the dose that produced 50% of antinociception (ED50) for each drug. The ED50 demonstrated the following rank order of potency, in the phase I: piroxicam > dexketoprofen > ketoprofen > parecoxib and in the phase II: piroxicam > ketoprofen > parecoxib > dexketoprofen. Pretreatment of the mice with L-NAME or 7-nitroindazol induced a significant increase of the analgesic power of the NSAIDs, with a significant reduction of the ED50. It is suggested that NO may be involved in both phases of the trial, which means that nitric oxide regulates the bioactivity of NSAIDs.

Immunological impact of canerpaturev (C-REV, formerly HF10), an oncolytic viral immunotherapy, with or without ipilimumab (Ipi) for advanced solid tumor patients (pts).

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 2610-2610 ◽  
Author(s):  
Takayuki Nakayama ◽  
Makiko Yamashita ◽  
Toshihiro Suzuki ◽  
Manami Shimomura ◽  
Tetsuya Nakatsura ◽  
...  
Keyword(s):  
T Cells ◽  
Phase I ◽  
Phase Ii ◽  
Solid Tumor ◽  
Peripheral Blood ◽  
Phase I Study ◽  
Phase Ii Study ◽  
Spontaneous Mutant ◽  
Local Site ◽  
Before And After

2610 Background: C-REV, an oncolytic, spontaneous mutant of Herpes Simplex Virus type 1 (HSV-1), is a cancer immunotherapy agent that combine direct tumor cell killing with immune modulation. A phase I study for solid tumors with cutaneous and/or superficial lesions treated with C-REV monotherapy and a phase II study for unresectable or metastatic melanoma treated with C-REV and Ipi combination therapy were conducted. Immune status of cancer pts before and after administration of C-REV with/without Ipi has been unclear. Methods: A phase I study (n = 6) included solid tumor pts with cutaneous and/or superficial lesions treated with C-REV monotherapy (1 x 106 and 1 x 107 TCID50/mL/dose; 4 injections q2-4wk). In phase II study (n = 28), C-REV (1 x 107 TCID50/mL/dose; 4 injections q1wk; then up to 15 injections q3wk) was injected into each tumor for advanced melanoma pts. Four Ipi infusions (3 mg/kg) were administered at q3wk. Immune-monitoring was conducted before and after treatment in tumor microenvironment usingpaired biopsy samples by multiplex immunohistochemistry (mIHC) and in peripheral blood by flow cytometry (FCM). Results: In the phase I study, significant infiltrations of CD8+and CD4+ T cells were observed at tumor local site statistically in three pts (60%) among five pts. In the phase II study, FCM of peripheral blood (n = 10) showed that the responders (irSD, n = 7, 70%) tend to express the higher levels of ICOS on CD4+ T cells as a pharmacodynamic biomarker of ipi monotherapy reported previously (Ng Tang D, et al. Cancer Immunol Res. 2013) and lower levels of PD-L1 on monocyte after two months of treatment. Moreover, mIHC analysis of paired tumor biopsy samples (n = 11) revealed that five pts (45%) among 11 pts were confirmed persistent infection of C-REV at the injected site by qPCR. Disease control rate of pts with the virus DNA detected on Days 85/169 was higher than that without it (100% [n = 5, irPR; 1, irSD; 4] vs. 33% [n = 6, irSD; 2, irPD; 4]). Furthermore, median OS of pts with or without the DNA detected was 342 or 251 days respectively. Conclusions: Our results suggest C-REV injection in the tumor local site have potential to enhance systemic immune response of Ipi. Clinical trial information: NCT03153085.

scholarly journals The Potential to Replace Cement with Nano-Calcium Carbonate and Natural Pozzolans in Cemented Mine Backfill

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Mohammed Hefni ◽  
Maaz A. Ali
Keyword(s):  
Calcium Carbonate ◽  
Unconfined Compressive Strength ◽  
Mercury Intrusion Porosimetry ◽  
Silica Sand ◽  
Strength Development ◽  
Microstructural Properties ◽  
Mine Backfill ◽  
Mercury Intrusion ◽  
Natural Pozzolans ◽  
Gold Tailings

The effectiveness of mine backfilling depends on the properties of its constituents. The high cost of cement, which is commonly used as a binder in mine backfill, has led researchers to seek alternatives to partially replace it with other binders. This study investigated the potential to use nano-calcium carbonate (NCC) and natural pozzolans (zeolite and pumice) along with Portland cement (PC) in mine backfill. Two types of experimental samples were prepared: (1) gold tailings and silica sand to investigate the effect of NCC and (2) nickel tailings to investigate the effect of natural pozzolans. The unconfined compressive strength (UCS) was measured for samples cured for up to 56 days. Moreover, selected samples were subject to mercury intrusion porosimetry to investigate microstructural properties. Results show that addition of NCC did not improve the UCS of backfill prepared with gold tailings and cured for 28 days, whereas a dosage of 1% NCC in backfill samples prepared with silica sand improved UCS by 20%, suggesting that the gold tailings negatively affected strength development. Natural pozzolans, in particular, 20% zeolite, had 24% higher UCS after 56 days of curing compared to samples prepared with PC and thus have the potential to partially replace cement in mine backfill.

scholarly journals Impact of a Process Change on Prevalence of Prescribed Unmeasurable Liquid Doses in a Neonatal Intensive Care Unit

2020 ◽  
Vol 25 (2) ◽  
pp. 96-103
Author(s):  
Stephanie O. Zahn ◽  
Jennifer H. Tobison ◽  
Amanda J. Place ◽  
Jamalyn N. Casey ◽  
Liz Hess ◽  
...  
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Neonatal Intensive Care ◽  
Primary Objective ◽  
Educational Process ◽  
System Level ◽  
Process Change ◽  
Discharge Medication ◽  
Before And After ◽  
Oral Liquid

OBJECTIVES Most prescribing through the electronic health record (EHR) in the NICU at St. Vincent Women's Hospital use a weight-based dosing calculator. Prescribers receive no alert if the resulting volume is unmeasurable. Study definition of measurable was a dose volume with a visible hash mark on an appropriately sized oral syringe. The primary objective was to compare the rate of unmeasurable oral liquid doses prescribed at discharge before and after implementation of educational process changes. Secondary objectives assessed patient and discharge medication characteristics in relation to the unmeasurable doses prescribed. METHODS This study was a 2-phase retrospective analysis of patients discharged from the NICU between January 1 and June 30, 2016 (phase I), and between October 1, 2017, and March 31, 2018 (phase II). Patients were included in the analysis if they were discharged on at least 1 oral liquid medication, excluding vitamins. Demographic and discharge medication information was collected. RESULTS There were 58 patients discharged on a total of 118 oral liquid medications in phase I and 63 patients discharged on a total of 111 oral liquid medications in phase II. Following implementation of the process change, the percentage of unmeasurable discharge prescriptions decreased from 27 (23%) to 5 (4.5%) (p < 0.001). CONCLUSIONS The educational process change implemented in the NICU effectively reduced the rate of unmeasurable doses prescribed at discharge from 1 in 4 to 1 in 25. Additional system-level changes may result in further reductions.

Effectiveness of a Glasgow Coma Scale Instructional Video for EMS Providers

2002 ◽  
Vol 17 (3) ◽  
pp. 142-146 ◽  
Author(s):  
Peter L. Lane ◽  
Amado Alejandro Báez ◽  
Thomas Brabson ◽  
David D. Burmeister ◽  
John J. Kelly
Keyword(s):  
Glasgow Coma Scale ◽  
Phase I ◽  
Phase Ii ◽  
Head Injuries ◽  
Instructional Video ◽  
Video Tape ◽  
Clinical Environment ◽  
Chi Square ◽  
Coma Scale ◽  
Before And After

AbstractIntroduction:The Glasgow Coma Scale (GCS) is the standard measure used to quantify the level of consciousness of patients who have sustained head injuries. Rapid and accurate GCS scoring is essential.Objective:To evaluate the effectiveness of a GCS teaching video shown to prehospital emergency medical services (EMS) providers.Methods:Participants and setting—United States, Mid-Atlantic region EMS providers. Intervention—Each participant scored all of the three components of the GCS for each of four scenarios provided before and after viewing a video-tape recording containing four scenarios. Design—Before-and-after single (Phase I) and parallel Cohort (Phase II). Analysis— Proportions of correct scores were compared using chi-square, and relative risk was calculated to measure the strength of the association.Results:75 participants were included in Phase I. In Phase II, 46 participants participated in a parallel cohort design: 20 used GCS reference cards and 26 did not use the cards. Before observing the instructional video, only 14.7% score all of the scenarios correctly, where as after viewing the video, 64.0% scored the scenarios results were observed after viewing the video for those who used the GCS cards (p = 0.001; RR = 2.0; 95% CI = 1.29 to 3.10) than for those not using the cards (p <0.0001; RR = 10.0; 95% CI = 2.60 to 38.50).Conclusions:Post-video viewing scores were better than those observed before the video presentation. Ongoing evaluations include analysis of longterm skill retention and scoring accuracy in the clinical environment.

scholarly journals Effect of esophageal acid exposure on the cortical swallowing network in healthy human subjects

2009 ◽  
Vol 297 (1) ◽  
pp. G152-G158 ◽  
Author(s):  
Mark Kern ◽  
Krisna Chai ◽  
Adeyemi Lawal ◽  
Reza Shaker
Keyword(s):  
High Resolution ◽  
Phase I ◽  
Phase Ii ◽  
Brain Activity ◽  
Cortical Activity ◽  
Esophageal Acid Exposure ◽  
Acid Exposure ◽  
Acid Perfusion ◽  
Phase Ii Studies ◽  
Before And After

Recent studies have demonstrated common cortical activity regions associated with esophageal acidification and swallowing. The effect of sensory signals imparted on these regions by esophageal acidification on swallow-related brain activity has physiological and clinical ramifications. Our aim in this study was to determine the effect of prior, unperceived esophageal acid exposure on cortical activity associated with swallowing. Functional magnetic resonance imaging (fMRI) techniques monitored brain activity associated with volitional swallowing before and after subliminal esophageal acid stimulation. Studies were carried out in two phases. In phase I (15 healthy, right-handed subjects, age 21–49 yr, 7 female) using whole brain imaging, we documented the potentiating effects of esophageal acidification alone on swallow-related cortical activity. In phase II (10 healthy, right-handed subjects, age 20–54 yr, 5 female) using high-resolution fMRI, we measured swallow-induced regional brain activity within the cortical swallowing network before and after esophageal acidification. Unlike the phase I studies, we also tested the effect of saline perfusion alone on the cortical swallowing network in the phase II studies. Because of constraints imposed by high-resolution MRI for region-of-interest (ROI) analysis, we studied only the left hemisphere in this phase. None of the subjects developed heartburn during acid perfusion. In phase I, the number of swallow-induced activated voxels increased by 43% following esophageal acid stimulation (preacid, 44 ± 3 voxels; postacid, 63 ± 6 voxels; means ± SE, P < 0.05) In phase II, contrary to saline perfusion, ROI analysis showed significantly increased regional swallow-related fMRI activity volumes as well as percent maximum signal change after esophageal acid perfusion in cingulate, prefrontal, insula, and sensory/motor regions ( P < 0.05). The precuneus showed no significant change. We concluded that subliminal esophageal acid stimulation has a potentiating effect on the cortical swallowing network in healthy individuals.

scholarly journals Assessing Medical Student’s Ability to Interpret Traumatic Injuries on Computed Tomography Before and After the Third Year Clerkships

2018 ◽  
Vol 11 (4) ◽  
pp. 91-94
Author(s):  
Brady Werth ◽  
Barbara Nguyen ◽  
Jeanette Ward ◽  
Jared Reyes ◽  
Stephen D. Helmer ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Phase I ◽  
Phase Ii ◽  
Radiographic Images ◽  
Skill Levels ◽  
Traumatic Injuries ◽  
Pelvic Injuries ◽  
Before And After ◽  
Life Threatening ◽  
Prospective Study Design

Introduction. Exposure to radiologic images during clinical rotationsmay improve students’ skill levels. This study aimed to quantifythe improvement in radiographic interpretation of life-threateningtraumatic injuries gained during third year clinical clerkships (MS-3). Methods. We used a paired-sample prospective study design tocompare students’ accuracy in reading computed tomography (CT)images at the beginning of their third year clerkships (Phase I) andagain after completion of all of their third year clerkships (Phase II).Students were shown life-threatening injuries that included head,chest, abdomen, and pelvic injuries. Overall scores for Phase II werecompared with Phase I, as well as sub-scores for each anatomicalregion: head, chest, abdomen, and pelvis. Results. Only scores from students participating in both Phase Iand Phase II (N = 57) were used in the analysis. After completingtheir MS3 clerkship, students scored significantly better overall andin every anatomical region. Phase I and Phase II overall mean scoreswere 1.2 ± 1.1 vs. 4.6 ± 1.8 (p < 0.001). Students improved the mostwith respect to injuries of the head and chest and the area of leastimprovement was in interpreting CT scans of the abdomen. Althoughimprovements in reading radiographic images were noted after theclerkship year, students accurately diagnosed only 46% of life-threateningimages on CT scan in the trauma setting. Conclusions. These results indicated that enhanced education isneeded for medical students to interpret CT scans.Kans J Med 2018;11(4):91-94.

Monitoring the Effectiveness of Hospital Cleaning Practices by Use of an Adenosine Triphosphate Bioluminescence Assay

2009 ◽  
Vol 30 (7) ◽  
pp. 678-684 ◽  
Author(s):  
John M. Boyce ◽  
Nancy L. Havill ◽  
Diane G. Dumigan ◽  
Michael Golebiewski ◽  
Ola Balogun ◽  
...  
Keyword(s):  
Phase I ◽  
Adenosine Triphosphate ◽  
Phase Ii ◽  
Relative Light Unit ◽  
Surface Samples ◽  
Before And After ◽  
Atp Bioluminescence ◽  
Bioluminescence Assay ◽  
Atp Bioluminescence Assay ◽  
Hospital Cleaning

Objective.To evaluate the usefulness of an adenosine triphosphate (ATP) bioluminescence assay for assessing the efficacy of daily hospital cleaning practices.Design.A 2-phase prospective intervention study.Setting.A university-affiliated community teaching hospital.Methods.During phase I of our study, 5 high-touch surfaces in 20 patient rooms were sampled before and after daily cleaning. Moistened swabs were used to sample these surfaces and were then plated onto routine and selective media, and aerobic colony counts were determined after 48 hours of incubation. Specialized ATP swabs were used to sample the same high-touch surfaces in the 20 patient rooms and were then placed in luminometers, and the amount of ATP present was expressed as relative light units. During phase II of our study, after in-service housekeeper educational sessions were given, the housekeepers were told in advance when ATP readings would be taken before and after cleaning.Results.During phase I, the colony counts revealed that the 5 high-touch surfaces were often not cleaned adequately. After cleaning, 24 (24%) of the 100 surface samples were still contaminated with methicillin-resistantStaphylococcus aureus, and 16 (16%) of the 100 surface samples still yielded vancomycin-resistant enterococci. ATP readings (expressed as relative light units) revealed that only bathroom grab bars and toilet seats were significantly cleaner after daily cleaning than before. During phase II, a total of 1,013 ATP readings were obtained before and after daily cleaning in 105 rooms. The median relative light unit was significantly lower (ie, surfaces were cleaner) after cleaning than before cleaning for all 5 high-touch surfaces.Conclusions.Suboptimal cleaning practices were documented by determining aerobic colony counts and by use of an ATP bioluminescence assay. ATP readings provided quantitative evidence of improved cleanliness of high-touch surfaces after the implementation of an intervention program.

Bewegungstherapie und körperliche Aktivität bei Patienten mit Herzinsuffizienz

Praxis ◽  
2018 ◽  
Vol 107 (17-18) ◽  
pp. 951-958 ◽  
Author(s):  
Matthias Wilhelm
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Körperliche Aktivität ◽  
Phase Iii

Zusammenfassung. Herzinsuffizienz ist ein klinisches Syndrom mit unterschiedlichen Ätiologien und Phänotypen. Die überwachte Bewegungstherapie und individuelle körperliche Aktivität ist bei allen Formen eine Klasse-IA-Empfehlung in aktuellen Leitlinien. Eine Bewegungstherapie kann unmittelbar nach Stabilisierung einer akuten Herzinsuffizienz im Spital begonnen werden (Phase I). Sie kann nach Entlassung in einem stationären oder ambulanten Präventions- und Rehabilitationsprogramm fortgesetzt werden (Phase II). Typische Elemente sind Ausdauer-, Kraft- und Atemtraining. Die Kosten werden von der Krankenversicherung für drei bis sechs Monate übernommen. In erfahrenen Zentren können auch Patienten mit implantierten Defibrillatoren oder linksventrikulären Unterstützungssystemen trainieren. Wichtiges Ziel der Phase II ist neben muskulärer Rekonditionierung auch die Steigerung der Gesundheitskompetenz, um die Langzeit-Adhärenz bezüglich körperlicher Aktivität zu verbessern. In Phase III bieten Herzgruppen Unterstützung.

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