2. Upper arm with intact skin, i.e. without areas of breached or injured skin visible, for ABP measurements,
3. 24h mean wake SBP \>145mmHg from 24hr-ABPM readings confirmed per data base query within the past 12 months prior to enrollment into Phase 1 and across two subsequent 24hr-ABP sessions during Phase 1,
4. Decline of \<10% between mean day time and night time systolic pressures from 24hr-ABPM readings confirmed per data base query within the past 12 months prior to enrollment into Phase 1 and across two subsequent 24hr-ABP sessions during Phase 1,
2. Upper arm with intact skin, i.e. without areas of breached or injured skin visible, for ABP measurements,
3. Healthy (as assessed by health history, physical exam and screening lab work),
4. 24h mean wake SBP \<130mmHg quantified per 24hr-ABPM,
5. Own a smartphone. 4.3.3 Inclusion Cohort 3 (control): matched dipping hypertensives 'DHT'
1\) \>18 years of age, 2) Upper arm with intact skin, i.e. without areas of breached or injured skin visible, for ABP measurements,
1. 24h mean wake SBP \>145mmHg from 24hr-ABPM readings,
2. Decline of \>10% between mean day time and night time systolic pressures from 24hr-ABPM readings,
3. Own a smartphone.
You may not be if
1. Known history of severe psychiatric or cognitive conditions, for example mania, schizophrenia, or mental retardation.
2. Shift work, defined as recurring work between 22:00-05:00,
3. History of clinically significant obstructive sleep apnea;
4. Urine creatinine \> 1.5 mg/dl in men or \>1.3 mg/del in women,
5. Significant liver disease (\>3x upper limit of normal),
6. Diabetes mellitus,
7. Transmeridian travel across ≥2 time zones in the month prior to ABP sessions,
8. Planned transmeridian travel across more than ≥2 time zones during the planned study activities;
9. \> 2 drinks of alcohol per day;
10. Use of illicit drugs which affect blood pressure;
11. Use of pacemaker or implantable Cardioverter Defibrillator, (ICD);
12. Bilateral mastectomy;
13. Hypotension, defined as 90/60 mmHg assessed during the screening visit from ≥ 3 in-office measurements initiated after 10 minutes in seated upright position with 5 minute intervals between measurements;
14. History of Raynaud's phenomenon;
15. Known allergy against natural latex rubber (contained in ABP bladder and tubing);
16. Nursing or pregnant females.
1. History of severe psychiatric illness or cognitive conditions, for example ( mania, schizophrenia, or mental retardation;
2. Shift work, defined as recurring work between 22:00-05:00;
3. Clinically significant obstructive sleep apnea as assessed per WatchPAT device;
4. Urine creatinine \> 1.5 mg/dl in men or \>1.3 mg/del in women;
5. Significant liver disease (\>3x upper limit of normal);
6. Diabetes mellitus;
7. Past diagnosis of gastroesophageal reflux disease,
8. Transmeridian travel across ≥2 time zones in the two weeks before the 48hr deep phenotype sessions;
9. Frequent transmeridian flyer (≥2 flights per month) across more than ≥2 time zones during the 12 months of study activities;
10. Use of oral or intravenous antibiotics in the 6 months prior to enrollment;
11. Any contraindication listed below in the separate paragraph "Contraindications for the use of CorTemp® Disposable Temperature Sensors";
12. Subjects, who have received an experimental drug, used an experimental medical device within 30 days prior to screening, or who gave a blood donation of ≥ one pint within 8 weeks prior to screening;
13. \> 2 drinks of alcohol per day;
14. Use of illicit drugs which affect blood pressure;
15. Nursing or pregnant (pregnancy will be repeatedly assessed at the beginning of each of the four inpatient visits, i.e. prior to the start of blood draws);
16. Use of pacemaker or implantable Cardioverter Defibrillator, (ICD)
17. Bilateral mastectomy;
18. Hypotension, defined as 90/60 mmHg assessed during the screening visit from ≥ 3 in-office measurements initiated after 10 minutes in seated upright position with 5 minute intervals between measurements;
19. History of Raynaud's phenomenon;
20. Known allergy against natural latex rubber (contained in ABP bladder and tubing);
21. Subjects taking medication with alpha-blockers;
22. History of clinically significant arrhythmias;
23. Subjects with a history of being particularly susceptible to vomiting or nausea;
