Human physical condition RF sensing at THz range.

The skin response to high radio frequency has been associated with the human physical condition and most prominently with the stress. The objective of this study is to investigate the possibility to detect mental and light physical stress through the measurement of skin reflectance in the mm-wave/sub-THz band. Two frequency bands have been considered, 75-110 GHz (Band-I) and 325-500 GHz (Band-II), while the measurements have been performed in the three different locations, the arm, the dorsal side of the hand and the fingertip. The measurement setup is discussed in detail and the reflectance spectrum is demonstrated. The results illustrate a difference in skin reflectance under rest and stress in Band-II which ranges from 3.5 dB at the finger to 7 dB at the hand. The outcomes of this study indicate the feasibility of stress detection through skin reflectance measurement and serve as a suggestion for deeper exploration of higher frequency bands.

Blood stream infections in renal transplant recipients: a single-center study.

INTRODUCTION: Bacteremias among renal transplant recipients are more frequent as a result of immunosuppression. They are considered extremely high-risk because they are correlated with decreased allograft and recipient survival. PATIENTS AND METHODS: All episodes of bacteremia among renal transplant recipients were documented following review of medical records, from January 2010 to May 2013. RESULTS: In total 26 episodes of bacteremia were observed in 22 patients. Gram negative bacteremia was identified in 73% (19/26) cases. Pathogens according to their frequency were the following Escherichia coli (6/26, 23%), Klebsiella pneumonia (5/26, 19%), Pseudomonas aeruginosa (3/26, 11%), Staphylococcus epidermidis (3/26, 11%), Acinetobacter baumanni (2/26, 7.7%), Enterococcus faecalis (2/26, 7.7%). The first trimester post renal transplantation 18 episodes (69%) of bacteremia were presented that were not correlated to indwelling urinary catheter or stent. Positive urinary culture with the same pathogen was recognized in 13 patients. All recipients manifested fever, eight recipients had leucocytosis and three cases were complicated by septic shock. Immediate resuscitation with intravenous fluids and non-nephrotoxic antibiotic regimen was initiated. Acute renal allograft dysfunction (defined as an increase in serum creatinine more than 0.5 mg/dL from baseline) was observed in five patients and was restored following infection resolution. CONCLUSION: Increased prevalence of bacteremia in renal transplant recipients is attributed to immunosuppression and usually bacteremic episodes follow urinary tract infection. The commonest pathogens are Gram negative bacteria with E. coli the most frequent. Early detection and proper management are important as bacteremia affects renal allograft and recipient survival.

Recurrent varicose veins after surgery: a new appraisal of a common and complex problem in vascular surgery.

OBJECTIVE: To assess the true incidence, the reflux patterns and the mechanisms responsible for recurrent varicose vein disease according to current definitions and guidelines. PATIENTS AND METHODS: Ninety-three patients (69 female, 24 male, mean age: 48 years) were prospectively evaluated pre- and postoperatively (1 month and 5 years), using clinical and colour duplex examination of both lower limbs. The CEAP score and its modification for recurrence (REVAS) were used for classification. RESULTS: In 113 operated lower limbs, 28 (25%) were found to have a recurrence, 20 of which were symptomatic (20/28, 72%). However, in this group, the mean severity score decreased significantly from 6.5 (SD 3.1) to 5.2 (SD 2.8) (p<0.001, paired t-test). The correlation between the type and cause of recurrence revealed: (1) true recurrent varices in eight limbs (8/28, 29%), primarily caused by neovascularisation, (2) new varicose veins as a consequence of disease progression in seven limbs (7/28, 25%), (3) residual veins in three limbs (3/28, 11%) mainly due to tactical errors (e.g. failure to strip the GSV), (4) complex patterns in 10 limbs (10/28, 36%). In the limbs with recurrence, 42 sources of venous reflux were identified: (1) 19 new sites of venous reflux were due to disease progression (15% of the operated limbs), (2) 13 were caused by neovascularisation (11.5% of the operated limbs), (3) six resulted from tactical failures (5.3% of the operated limbs) and (4) four were due to technical failures (3.5% of the operated limbs). CONCLUSIONS: This study shows that the recurrence of varicose veins after surgery is not uncommon. However, the clinical condition of most affected limbs remains improved. Progression of the disease and neovascularisation are responsible for more than half of the recurrences. Rigorous evaluation of patients and assiduous surgical technique might reduce recurrence due to technical and tactical failures.