AIM-Harvard/TrialPanorama-filtered huggingface dataset:
Study NCT01083394 — intervention group
Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: Percutaneous Transluminal Angioplasty (PTA)
Description: Percutaneous transluminal angioplasty with conventional balloon or paclitaxel-eluting balloon
Study NCT01083394 — intervention group
Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: Percutaneous Transluminal Angioplasty (PTA)
Description: Percutaneous transluminal angioplasty with conventional balloon or paclitaxel-eluting balloon
Study NCT04158440 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: 4cycles(Toripalimab IV 240mg + platinum-based doublet chemotherapy)+13 cycles(Toripalimab IV 240mg); Biological: Toripalimab
Description: Biological: Toripalimab 240 mg by IV infusion every 3 weeks (Q3W), given on cycle day 1;Drug: Cisplatin 75 mg/m\^2 by IV infusion Q3W, given on cycle day 1;Drug: Corboplatin AUC 5 by IV infusion Q3W, given on cycle day 1;Drug: Pemetrexed 500 mg/m\^2 by IV infusion Q3W, given on cycle day 1. Given only to participants with nonsquamous NSCLC.Drug:Paclitaxel 175 mg/m\^2 by IV infusion Q3W;Drug:Docetaxel 60-75 mg/m\^2 by IV infusion Q3W
Study NCT04158440 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: 4cycles(Placebo + platinum-based doublet chemotherapy)+13 cycles(Placebo )
Description: Biological: Placebo by IV infusion every 3 weeks (Q3W), given on cycle day 1;Drug: Cisplatin 75 mg/m\^2 by IV infusion Q3W, given on cycle day 1;Drug: Corboplatin AUC 5 by IV infusion Q3W, given on cycle day 1;Drug: Pemetrexed 500 mg/m\^2 by IV infusion Q3W, given on cycle day 1. Given only to participants with nonsquamous NSCLC.Drug:Paclitaxel 175 mg/m\^2 by IV infusion Q3W;Drug:Docetaxel 60-75 mg/m\^2 by IV infusion Q3W
Study NCT01883843 — intervention group
Intervention type: DEVICE
Group type: ACTIVE_COMPARATOR
Intervention: sham tDCS + TOCT
Description: Every day will be given a continuous low-intensity stimulation of 0.5mA (for a current density of 60μA/cm2) only for 10 seconds at the beginning and at the end of the stimulation for 10 consecutive days after any rehabilitative treatment. The mounting of electrodes for sham stimulation is the same used for the experimental group.
Study NCT01883843 — intervention group
Intervention type: DEVICE
Group type: EXPERIMENTAL
Intervention: real tDCS + TOCT
Description: Every day will be given continuous stimulation duration of 15 minutes with intensity of 0.5 mA (for a current density of 60μA/cm2), generated by a constant current stimulator rechargeable batteries for 10 consecutive days after any rehabilitation treatment in the gym. Two sponge electrodes are placed, soaked in saline solution, fixed by an elastic band, the anode consists of an electrode oblong 8cm2 positioned at M1 area on the lower limb affection (following the medial sagittal axis, with the center of the electrode positioned at one centimeter laterally to the vertex) while the cathode (48cm2) is placed in the contralateral supraorbitale area as reference electrode. The current reaches 0.5mA and decreases with a ramp of 10 seconds.
Study NCT03441776 — intervention group
Intervention type: OTHER
Group type: OTHER
Intervention: Generalized Vestibular Rehabilitation Treatment
Description: These treatment visits are available twice a week and each visit lasts 45 minutes. Individuals receiving GVRT are allowed to choose the frequency at which they want to attend and the program is designed for each subject to complete 8 visits within a period between 4 and 8 weeks. The ideal number of patients receiving treatment at each class is from 3 to 6 but the system has capacity for a maximum of 8. GVRT is a standard of care treatment option and is not considered research.
Study NCT03441776 — intervention group
Intervention type: OTHER
Group type: OTHER
Intervention: Individualized Vestibular Rehabilitation Treatment
Description: Individuals receiving IVRT are scheduled depending on their individual needs and PT availability. These visits require one-on-one time with a PT. Individuals are commonly seen by the PT 3 times at two week intervals. These visits last 30 minutes and include PT evaluation designed to instruct patients on exercises for them to perform on their own. IVRT is a standard of care treatment option and is not considered research.
Study NCT04492839 — intervention group
Intervention type: DEVICE
Group type: EXPERIMENTAL
Intervention: Intestinal adsorbent
Description: Participants will consume the 15ml of the intestinal adsorbent (3.5 g Silicon dioxide in 100 ml Silicic acid gel, Preservatives: Sorbic acid (E 200), Sodium benzoate (E 211). ) three times daily for 10 days. There are no known side effects of the medical device. The product is a class IIa medical device under the European council directive and the product will be used within it's current indications.
Study NCT01074450 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Pramipexole Dihydrochloride
Description: 0.25 mg Tablet
Study NCT01074450 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Pramipexole Dihydrochloride
Description: 0.25 mg Tablet
Study NCT03879122 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Ipilimumab 5 MG/ML
Description: Ipilimumab will be administered on day 1 of each cycle every 3 weeks. In arm 3, ipilimumab should be started at least 2 weeks but no later than 120 days after surgical castration or the first dose of LHRH analogue. Patients should receive 2 doses of ipilimumab (6 weeks). It will be followed, 3 weeks later, by 3 cycles of docetaxel and by 2 additional doses of ipilimumab and 3 more cycles of docetaxel. Four weeks later, Nivolumab will be administered on day 1 every 2 weeks until a maximum of 24 doses (48 weeks)
Study NCT03879122 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Nivolumab 10 MG/ML
Description: Nivolumab will be administered every 2 weeks, until clinical progression or a maximum of 24 doses. Nivolumab should be started 4 weeks after the last dose of docetaxel, providing all the adverse effects have recovered, as if a new cycle of docetaxel were to be administered
Study NCT01923363 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Piperacillin/Tazobactam Standard Dose to High Dose
Description: Patients will receive a standard dose of piperacillin/tazobactam, then will have subsequent pharmacokinetic analyses on the blood concentrations drawn while on standard dose. Patients will be switched to higher dose after receiving the standard dose, with subsequent pharmacokinetic analyses performed on those blood concentrations while on higher dose. These pharmacokinetics of each dosing regimen will be compared.
Study NCT03879122 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Docetaxel
Description: Docetaxel should be given on day 1 every 21 days, for up to 6 cycles (1 cycle = 21 days). Docetaxel should be started within 7 working days from the date of randomization in the arm 1 and 2.~In arm 3, docetaxel will be given 3 weeks after the last dose of the previous treatment, providing all the side effects are grade ≤1.
Study NCT03879122 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Docetaxel
Description: Docetaxel should be given on day 1 every 21 days, for up to 6 cycles (1 cycle = 21 days). Docetaxel should be started within 7 working days from the date of randomization in the arm 1 and 2.~In arm 3, docetaxel will be given 3 weeks after the last dose of the previous treatment, providing all the side effects are grade ≤1.
Study NCT03879122 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: ADT (androgen deprivation therapy)
Description: Androgen deprivation therapy per the standard of care
Study NCT03879122 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: ADT (androgen deprivation therapy)
Description: Androgen deprivation therapy per the standard of care
Study NCT02779088 — intervention group
Intervention type: OTHER
Group type: ACTIVE_COMPARATOR
Intervention: exercise and nutrition
Description: Exercise:muscle strengthening exercise Nutrition: 7.2 g branched chain amino acid every day and 1200 mg Ca+800 IU Vitamin D3
Study NCT01923220 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: HO/02/02 20µg
Description: Interventions involving HO/02/02 20µg VS. Aloe Vera Jel (SOC). Treatment will be applied topically once daily
Study NCT01923220 — intervention group
Intervention type: OTHER
Group type: SHAM_COMPARATOR
Intervention: Aloe Vera Jel
Description: To be applied topically once daily
Study NCT01936688 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: MK-3222 200 mg
Description: MK-3222 200 mg administered SC.
Study NCT01936688 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: MK-3222 100 mg
Description: MK-3222 100 mg administered SC.
Study NCT02779088 — intervention group
Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: exercise and nutrition
Description: Exercise:muscle strengthening exercise Nutrition: 7.2 g branched chain amino acid every day and 1200 mg Ca+800 IU Vitamin D3
Study NCT00759265 — intervention group
Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: resistance training
Description: During 24 weeks, the patients of the intervention group will participate in a resistance training program. Two subsequent intervention programmes will be offered. Initially the first 12 week resistance trainings stage will aimed at improving function of lower leg muscles; subsequently a more extended programme affecting total limb musculature (lower- and upper leg) will be provided (also 12 weeks).~During these trainings period, patients will train 3 times a week; once a plenary training session of 1,5 hour provided by a physical therapist. And 2 trainings sessions of half an hour each, by them selves at home.
Study NCT01936688 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Placebo to MK-3222
Description: Matching placebo to MK-3222 administered SC.
Study NCT01936688 — intervention group
Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo to MK-3222
Description: Matching placebo to MK-3222 administered SC.
Study NCT01936688 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Placebo to Etanercept
Description: Matching placebo to etanercept for subcutaneous injection.
Study NCT02624063 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Daclatasvir + Sofosbuvir
Description: Sofosbuvir 400 mg tablet + Daclatasvir 60 mg tablet oral dosing once daily for 12 weeks
Study NCT02624063 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Simeprevir + Sofosbuvir
Description: Sofosbuvir 400 mg tablet + Simeprevir 150 mg tablet oral dosing once daily for 12 weeks
Study NCT01936688 — intervention group
Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo to Etanercept
Description: Matching placebo to etanercept for subcutaneous injection.
Study NCT01936688 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Etanercept 50 mg
Description: Etanercept 50 mg for subcutaneous injection.
Study NCT02005445 — intervention group
Intervention type: DEVICE
Group type: EXPERIMENTAL
Intervention: CPAP
Description: Continuous positive airway pressure
Study NCT02005445 — intervention group
Intervention type: BEHAVIORAL
Group type: SHAM_COMPARATOR
Intervention: HLSE
Description: Healthy living and sleep education
Study NCT01443754 — intervention group
Intervention type: PROCEDURE
Intervention: LIMA-LAD surgical revascularization
Description: Off-pump coronary artery bypass (OPCAB) in which coronary revascularization is performed on the beating heart will be followed, the choice of the technical solutions being left at the discretion of the cardiac surgeon:~* use of a left anterior small thoracotomy (LAST), LIMA harvesting using thoracoscopic methods and manual anastomosis of the LIMA-LAD using a stabilization device;~* minimally invasive direct coronary bypass surgery (MIDCAB). The procedures can be performed alone or in combination with one another.
Study NCT03587025 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Amitriptyline
Description: Amitriptyline compared with placebo for preemptive analgesia in women after abdominal hysterectomy.
Study NCT03587025 — intervention group
Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo
Description: Placebo
Study NCT03179111 — intervention group
Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: Pneumoperitoneum Pressure
Description: There will be two arms in this study. The participants recruited for this study are those who have been screened and planned for elective bariatric surgery.The pneumoperitoneum pressure will be adjusted to either 8-10mmHg or 12-15mmHg until a clear operating field is obtained by the surgeon. Low pneumoperitoneum pressure has been expected to give a clearer and better surgical view than standard pneumoperitoneum pressure. Participants under the low pressure group are expected to have lesser pain score on abdominal pain and shoulder tip pain as compared to participants in the standard pressure group.
Study NCT01610713 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: GW-1000-02
Description: Containing THC (27 mg/ml):CBD (25 mg/ml), in ethanol:propylene glycol (50:50) excipients, with peppermint oil (0.05%) flavouring. The maximum permitted dose of study medication was eight actuations (22 mg THC and 20 mg CBD) in any three hour period, and 48 actuations (130 mg THC and 120 mg CBD) in any 24 hour period.
Study NCT03916185 — intervention group
Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: RSV ΔNS2/Δ1313/I1314L Vaccine
Description: 10\^6 plaque-forming units (PFU); administered as nose drops
Study NCT03916185 — intervention group
Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: RSV 6120/ΔNS2/1030s Vaccine
Description: 10\^5 plaque-forming units (PFU); administered as nose drops
Study NCT03916185 — intervention group
Intervention type: BIOLOGICAL
Group type: EXPERIMENTAL
Intervention: RSV 276 Vaccine
Description: 10\^5 plaque-forming units (PFU); administered as nose drops
Study NCT03916185 — intervention group
Intervention type: BIOLOGICAL
Group type: PLACEBO_COMPARATOR
Intervention: Placebo
Description: Administered as nose drops
Study NCT00503776 — intervention group
Intervention type: BEHAVIORAL
Group type: ACTIVE_COMPARATOR
Intervention: exercise intervention
Description: Patients undergo low weight resistance training.
Study NCT00503776 — intervention group
Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: exercise intervention
Description: Patients undergo low weight resistance training.
Study NCT00503776 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: amifostine trihydrate
Description: Given subcutaneously
Study NCT00503776 — intervention group
Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: therapeutic dietary intervention
Description: Patients undergo specialized nutrition therapy (SNT) including dietitian counseling and calorie goal instruction.
Study NCT00503776 — intervention group
Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: therapeutic dietary intervention
Description: Patients undergo specialized nutrition therapy (SNT) including dietitian counseling and calorie goal instruction.
Study NCT04557514 — intervention group
Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: platelet rich plasma injection in post burn facial scar
Description: 2 spins>>>~1. st spin (separate plasma from blood) 2500 for 10 minutes~2. nd spin (separate platelet rich part of plasma) 1500 for 10 minutes Taking lower part (platelet rich plasma ) Injection under scar after rigotomy
Study NCT04557514 — intervention group
Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: fat injection in post burn facial scar
Description: Anesthesia : general or local Lipoaspirate from abdomen or thigh using adrenaline(1\\1000000) + ringer lactate + zylocaine Liposuction by canula no4 Sediment 3 layers : taking mid layer of fat and omit uppermost and lowermost layers Lipoinjection in fan shaped manner 10-20 cc according to site affected by canula no 1 .
Study NCT02471560 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: dimethyl fumarate
Description: As per the prevailing local label.
Study NCT02471560 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: injectable MS DMT
Description: As described above.
Study NCT02324205 — intervention group
Intervention type: DEVICE
Group type: EXPERIMENTAL
Intervention: DBT and FFDM
Description: Subjects underwent breast imaging using each device: DBT and FFDM.
Study NCT02778555 — intervention group
Intervention type: BEHAVIORAL
Intervention: Questionnaires
Study NCT03585036 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: dexketoprofen
Description: Drug: dexketoprofen Women will receive oral dexketoprofen 25mg 2 hours before the procedure~Drug: Placebo 1 Women will receive an oral placebo similar to Tramadol 2 hours before the procedure.
Study NCT03585036 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Tramadol
Description: Drug: Tramadol Women will receive oral Tramadol 100 mg 2 hours before the procedure~Drug: Placebo 2 Women will receive an oral placebo similar to dexketoprofen 2 hours before the procedure
Study NCT03585036 — intervention group
Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo
Description: Drug: Placebo 1 Women will receive an oral placebo similar to Tramadol 2 hours before the procedure.~Drug: Placebo 2 Women will receive an oral placebo similar to dexketoprofen 2 hours before the procedure
Study NCT00531557 — intervention group
Intervention type: DRUG
Group type: OTHER
Intervention: Darunavir ritonavir
Study NCT02382029 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Clonazepam
Description: Active medical treatment for burning mouth syndrome
Study NCT02382029 — intervention group
Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: acupuncture
Description: Traditional chinese acupuncture
Study NCT03118427 — intervention group
Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: zero-fluoroscopy 3D navigation
Description: Pacemaker implantation will be performed without fluoroscopy using 3D navigation systems.
Study NCT03118427 — intervention group
Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: conventional x-ray navigation
Description: Pacemaker implantation will be performed with fluoroscopy using conventional X-ray navigation.
Study NCT01572363 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Sildenafil
Description: 50 mg once
Study NCT02152371 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Dulaglutide
Description: Administered SQ
Study NCT01443754 — intervention group
Intervention type: PROCEDURE
Intervention: PCI
Description: State of the art drug eluting stent (DES)-based percutaneous coronary intervention will be used by each participating site, according to current international guidelines.~Zotarolimus, everolimus or sirolimus drug-eluting stents will be used in all sites.
Study NCT01314443 — intervention group
Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Nicotine Replacement Therapy (NRT)
Description: Participants will quit smoking with nicotine patches
Study NCT01314443 — intervention group
Intervention type: DIETARY_SUPPLEMENT
Group type: EXPERIMENTAL
Intervention: Gamma-Tocopherol
Description: Participants will take gamma-tocopherol (500 mg/d) supplements for 7 days
Study NCT01314443 — intervention group
Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: Placebo
Description: Participants will take placebo for 7 days
Study NCT01314443 — intervention group
Intervention type: BEHAVIORAL
Group type: EXPERIMENTAL
Intervention: Smoking cessation
Description: Participants will quit smoking without any pharmacological aids
Study NCT02299609 — intervention group
Intervention type: OTHER
Group type: SHAM_COMPARATOR
Intervention: Ultrasound beams Philips HD11 XE®
Description: Ultrasound beams used during standard echocardiography
Study NCT02299609 — intervention group
Intervention type: OTHER
Group type: ACTIVE_COMPARATOR
Intervention: Ultrasound beams Philips HD11 XE®
Description: Ultrasound beams used during standard echocardiography
Study NCT02152371 — intervention group
Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Placebo
Description: Administered SQ
Study NCT02152371 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Insulin Glargine
Description: Administered SQ
Study NCT03140020 — intervention group
Intervention type: PROCEDURE
Intervention: Clipping
Description: During the microsurgical operation a titan clip will be placed round the aneurysm neck to exclude the aneurysm from the bloodflow and prevent fatal subarachnoidal hemorrhage.
Study NCT03140020 — intervention group
Intervention type: PROCEDURE
Intervention: Coiling
Description: Using a catheter technique the aneurysm dome will be filled up with coils to prevent subarachnoidal hemorrhage.
Study NCT03465202 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Capecitabine
Study NCT03041402 — intervention group
Intervention type: OTHER
Group type: ACTIVE_COMPARATOR
Intervention: PSP
Description: PSP, setting the inspiratory pressure support ≥8 cmH2O to obtain a tidal volume of 6-8 mL•kg-1 of body weight, the fastest rate of pressurization (0.0 sec) and I/E cycling at 35% of peak inspiratory flow
Study NCT03041402 — intervention group
Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: PSP
Description: PSP, setting the inspiratory pressure support ≥8 cmH2O to obtain a tidal volume of 6-8 mL•kg-1 of body weight, the fastest rate of pressurization (0.0 sec) and I/E cycling at 35% of peak inspiratory flow
Study NCT02152371 — intervention group
Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Insulin Glargine
Description: Administered SQ
Study NCT02152371 — intervention group
Intervention type: DRUG
Group type: EXPERIMENTAL
Intervention: Metformin
Description: Administered orally
Study NCT02152371 — intervention group
Intervention type: DRUG
Group type: PLACEBO_COMPARATOR
Intervention: Metformin
Description: Administered orally
Study NCT01028534 — intervention group
Intervention type: DRUG
Group type: ACTIVE_COMPARATOR
Intervention: Olmesartan and Azelnidipine
Description: 1. Olmesartan 20mg per day for 3 months and, if hypertension is not controlled, increase Olmesartan to 40mg per day for the next 3 months~2. Olmesartan 20mg per day for 3 months and, if hypertension is not controlled, add Azelnidipine 16mg per day for the next 3 months~3. Azelnidipine 16mg per day for 3 months, and, if hypertension is not controlled, add Olmesartan 20mg per day for the next 3 months
Study NCT03041402 — intervention group
Intervention type: OTHER
Group type: ACTIVE_COMPARATOR
Intervention: NAVA
Description: NAVA, adjusting the NAVA level in order to achieve a comparable peak EAdi (EAdipeak) as during PSP with a safety Paw upper limit of 30 cmH2O
Study NCT03041402 — intervention group
Intervention type: OTHER
Group type: EXPERIMENTAL
Intervention: NAVA
Description: NAVA, adjusting the NAVA level in order to achieve a comparable peak EAdi (EAdipeak) as during PSP with a safety Paw upper limit of 30 cmH2O