Low-cost, non-selective, solar-radiation detectors

The theory and basic design of a low-cost, flat-response thermoelectric detector is presented, which can be adapted for use as a pyranometer or net radiometer. This device can also be used as a submersible radiometer for radiation transmission measurements in water. The analysis allows the calculation of the responsivity and optimal design of a detector. Theoretical results are corroborated by experimental data obtained using a laboratory prototype.

Effect of salinity-concentration gradient on radiation transmission in salt-gradient ponds

In contrast to what is widely believed, a salinity gradient considerably affects the radiation transmission in salt-gradient ponds, by a degree which largely depends on the pond-water's spectral extinction characteristics.

Effects of molecular diffusion of salt in salt-gradient solar ponds

The effect of molecular diffusion of salt is not only significant for the smoothing process during the pond's establishment, but also for its operation. An analysis is presented to calculate the rate of salt transport within an isothermal liquid column, according to the molecular diffusion process. Salt-transport measurements in laboratory pond models provide experimental data in good agreement with the theoretical predictions.

Effect of 12-month intervention with low-dose atorvastatin on pulse wave velocity in subjects with type 2 diabetes and dyslipidaemia

Cardiovascular disease is the leading cause of morbidity and mortality in subjects with type 2 diabetes mellitus. Increased aortic stiffness, assessed with the carotid–femoral pulse wave velocity, is an independent risk factor for cardiovascular disease. Statins reduce effectively cardiovascular disease and mortality in high-risk patients. The aim of this prospective non-randomized, observational study was to examine the impact of treatment with either 10 mg atorvastatin plus diet or diet alone on carotid–femoral pulse wave velocity in subjects with type 2 diabetes mellitus and dyslipidaemia. A total of 79 subjects with type 2 diabetes mellitus and dyslipidaemia were included; 46 subjects were treated with atorvastatin 10 mg daily plus diet and 33 were managed by diet alone for 12 months. Carotid–femoral pulse wave velocity and carotid–radial pulse wave velocity were measured using applanation tonometry. In the atorvastatin-treated group, carotid–femoral pulse wave velocity reduced significantly during the study and there was a trend for reduction in the carotid–radial pulse wave velocity. Total cholesterol, low-density lipoprotein cholesterol, triglycerides and C-reactive protein were reduced only in the atorvastatin-treated participants. No significant changes were found in body mass index, blood pressure, heart rate, diabetes control and high-density lipoprotein cholesterol in either study group. Treatment with low-dose atorvastatin for 12 months improves carotid–femoral pulse wave velocity in subjects with type 2 diabetes mellitus and dyslipidaemia. © The Author(s) 2018

Factors associated with sclerostin levels – A calcification inhibitor – In individuals with type 2 diabetes mellitus; Is autonomic neuropathy the missing link?

Background: Sclerostin inhibits bone formation and its expression is upregulated in the vasculature during the arterial calcification process as a counterregulatory mechanism preventing further calcification. Lower extremity arterial calcification (LEAC) is common in neuropathic patients with type 2 diabetes (T2DM). Herein, we investigated for associations between plasma sclerostin levels and diabetic neuropathy as well as LEAC in subjects with T2DM. Methods: A total of 74 individuals with and 76 without T2DMwere recruited. Plasma sclerostin levels were measured by ELISA. Diagnosis of cardiac autonomic neuropathy (CAN) was based on the battery of the four autonomic tests, while of somatosensory peripheral neuropathy (DPN) on neuropathy symptom score and neuropathy disability score. LEAC was assessed with conventional ankle and foot x-rays. Results: Plasma sclerostin levels were higher in participants with LEAC vs. those without LEAC in both diabetes and non-diabetes cohorts (p = 0.035 and p = 0.003, respectively). In the diabetes cohort, patients with CAN, but not with DPN, had higher sclerostin levels when compared with those without CAN (p < 0.001). Multivariate analysis in the diabetes cohort demonstrated that sclerostin levels were associated positively with CAN and LEAC, while in the non-diabetes cohort there was a trend for a positive association with male gender and presence of LEAC. Conclusion: Plasma sclerostin levels are increased in individuals with LEAC irrespectively of diabetes status. In addition, plasma sclerostin concentrations are associated independently with LEAC and CAN in people with T2DM. © 2020 Elsevier Inc

The association of diabetic microvascular and macrovascular disease with cutaneous circulation in patients with type 2 diabetes mellitus

Aims: To study the impact of diabetic neuropathy, both peripheral sensorimotor (DPN) and cardiac autonomic neuropathy (CAN), on transcutaneous oxygen tension (TcPO2) in patients with type 2 diabetes mellitus (T2DM). Methods: A total of 163 participants were recruited; 100 with T2DM and 63 healthy individuals. Peripheral arterial disease (PAD) was defined as ankle-brachial index (ABI) values ≤0.90. Diagnosis of DPN was based on neuropathy symptom score and neuropathy disability score (NDS), while diagnosis of CAN on the battery of the cardiovascular autonomic function tests. TcPO2 was measured using a TCM30 system. Results: Patients with T2DM had lower TcPO2 levels when compared with healthy individuals. Among the diabetic cohort, those who had either PAD, DPN or CAN had significantly lower TcPO2 values than participants without these complications. Multivariate linear regression analysis, after controlling for diabetes duration, diastolic blood pressure, HbA1c, albumin to creatinine ratio and CAN score, demonstrated that TcPO2 levels were significantly and independently associated with current smoking (p = 0.013), ABI (p = 0.003), and NDS (p = 0.013). Conclusion: Presence of DPN is independently associated with impaired cutaneous perfusion. Low TcPO2 in subjects with DPN may contribute to delay in healing of diabetic foot ulcers, irrespectively of PAD. © 2018 Elsevier Inc

Association of Circulating Osteopontin Levels With Lower Extremity Arterial Disease in Subjects With Type 2 Diabetes Mellitus: A Cross-Sectional Observational Study

Osteopontin (OPN) is involved in the atherosclerotic and inflammatory process. In this article, we examined the relationship between circulating OPN levels with lower extremity arterial disease (LEAD) in individuals with type 2 diabetes mellitus (T2DM). Seventy individuals with T2DM and 66 individuals without T2DM were recruited. Diagnosis of LEAD was based on the absence of triphasic waveform on the pedal arteries. Plasma OPN levels were determined by Luminex Multiplex immunoassay. LEAD was present in 34 (48.6%) patients with T2DM. In the diabetes cohort, individuals with LEAD had higher plasma OPN concentrations than those without LEAD (geometric mean [95% confidence intervals]; 43.4 [37.5-50.4] vs 26.1 [22.9-29.8] ng/mL, respectively, P <.001). Multivariable analysis showed that presence of LEAD independently associated with higher OPN levels in subjects with T2DM, with marginal statistical significance (P =.049). In both cohorts, plasma OPN concentrations were negatively associated with ankle-brachial index values (P <.05). In the total sample, there was a gradual increase of OPN levels across subgroups with triphasic, biphasic, and monophasic/blunted waveforms (P <.001). In conclusion, plasma OPN levels are associated with the presence and severity of LEAD in subjects with T2DM. Further studies are needed to investigate the role of OPN in the pathogenesis and progression of LEAD. © The Author(s) 2020