Terahertz antenna with tunable filtering.

A terahertz (THz) antenna with tunable filtering is designed and numerically studied. A slotted monopole radiator with defected ground structure is used for operating with wideband response with an impedance bandwidth in the range of 3.80-11.98 THz for S 11≤-10d B. A slot is engraved in the radiator for obtaining the filtering characteristics in the antenna response. By varying its chemical potential, the frequency band 5.05-6.69 THz with graphene material can provide the tunability in the frequency and bandwidth of the filtered band in the antenna response. Furthermore, the antenna can provide radiation efficiency of more than 90% and gain with a peak value of 6.6 dBi in the passband.

The adjuvant effect of hypertension upon diabetic peripheral neuropathy in experimental type 2 diabetes.

Type 2 diabetes (DM) is the most common cause of peripheral neuropathy in the Western world. A comorbidity, hypertension, has been speculated to contribute to initiation or worsening of diabetic peripheral neuropathy. We studied adult rat models using genetic strains with DM (Zucker Diabetic Fat rats)±hypertension (HTN (ZSF-1 rats)) to investigate the relative contributions of DM and HTN and the potential for additive effects of HTN upon existing DM for the development of peripheral neuropathy. Long duration sensorimotor behavioral and electrophysiological testing was complemented by histological and molecular methods. Only DM led to tactile and thermal hyperalgesia and affected motor nerve electrophysiology. Although DM led to marked loss of sensory amplitudes and to sensory conduction slowing, a mild additive effect from HTN contributed after 6months of DM with worsening of slowing of sensory nerve conduction velocities, but without effect upon sensory amplitudes. At the sensory dominant sural nerve, mild (<10%) but greater degrees of myelin thinning were noted with DM and HTN combined, suggesting a mild additive effect. Matrix metalloproteinase (MMP) expression was increased only at the sural nerve in the presence of HTN with co-localization to Schwann cells and myelin. The effects of DM and HTN upon peripheral nerve are dissimilar, with HTN contributing to MMP upregulation at the sites of myelin thinning at sensory nerve fibers, potentially worsening comorbid DM. Together, our results indicate that HTN has a mild additive contribution to diabetic peripheral neuropathy at sensory peripheral nerve fibers manifesting with the loss of myelin thickness.