Microwave sensor for the investigation of glucose-dependent reflection properties in aqueous samples

Abstract

The reported paper presents the development of a microwave sensor with a resonant frequency 2.4?GHz. The sensor is also demonstrated in vitro to investigate the variation in its response as a function of glucose concentration. The sensor could be used for the monitoring of blood glucose level in diabetics through non-invasive technology. The approach followed is based on the notion that, change in glucose concentration in the blood affects dielectric properties of blood which in turn produce an impact on reflection properties of the sensor. This effect on response of sensor will be ultimately used to estimate blood glucose concentration. The design specifications considered for the development of sensor are defined in the paper. The experimental setup for in vitro experiment and procedure employed for the investigation of the reflection properties of the sensor as a function of glucose concentration are also discussed in detail. The shift in resonance frequency and the change in the magnitude of the reflection coefficient of proposed sensor have been observed. The reported measurement results are the preliminary results in exploring the implementation of proposed sensor for non-invasive blood glucose monitoring.     

Hyperammonemic coma in a post-partum patient with undiagnosed urea cycle defect

Urea cycle disorders (UCD) are common during neonatal period, and it is rarely reported in adults. We are reporting a patient presenting with post-partum neuropsychiatric symptoms rapidly progressing to coma. Markedly raised serum ammonia level on presentation with an initial normal magnetic resonance imaging (MRI) of brain and normal liver function tests led to the suspicion of UCD, which was confirmed on the basis of urine orotic acid and elevated serum amino acid levels. We had to resort to hemodialysis to correct the hyperammonemic coma, which was unresponsive to conventional anti-ammonia measures. She exhibited remarkable improvement with a progressive decline in serum ammonia with repeated hemodialysis and made a full recovery. Timely diagnosis and early institution of hemodialysis in the setting of a poor neurological status maybe considered a suitable treatment option.     

Cognitive screening for adult psychiatric outpatients: Comparison of the Cognivue® to the Montreal Cognitive Assessment

In this editorial we comment on the article by Cahn-Hidalgo D published in a recent issue of the World Journal of Psychiatry 2020; 10(1); 1-11. We focus on the importance of utilizing psychometrically valid cognitive screening tools when assessing for cognitive decline in older adults in a psychiatric outpatient setting. We compared the use of Cognivue^® to use of the montreal cognitive assessment (MoCA) as a cognitive screening tool. A total of 58 patients aged 55 and over participated in this comparison study. Patients completed cognitive screening on Cognivue^®, a new Food and Drug Administration-cleared computer screening device, and the MoCA. The results of patient performance using these two instruments were analyzed. Sixteen (28%) patients screened negative for cognitive impairment on both assessments. Forty-two (72%) patients screened positive on one or both of the assessments. There was 43% agreement between Cognivue^® and the MoCA in identifying patients with cognitive impairment, and individual subtests were weakly correlated. The MoCA was determined to be the preferred instrument due to its high sensitivity and specificity (100% and 87%, respectively) when screening for cognitive impairment. We propose that the use of Cognivue^® cognitive screening tool be closely reviewed until more research proves that the test meets the standards for reliability and validity. It is important for clinicians to remember that screeners should not be used to diagnosis patients with neurocognitive disorders; instead, they should be used to determine whether further evaluation is warranted. Additionally, misdiagnosing of neurocognitive disorders can pose unnecessary psychological and emotional harm to patients and their families and also lead to incorrect treatment and undue healthcare costs.     

Gamma-radiated biochar carbon for improved supercapacitor performance

Biochar carbon YP-50 exposed to gamma radiation at 50 kGy, 100 kGy, and 150 kGy was used as an electrode for an electric double-layer capacitor. The gamma radiation affected the pore structure and pore volume of the biochar electrodes. The optimized surface morphology, pore structure, and pore volume of the biochar with an irradiation dose of 100 kGy showed outstanding specific capacitance of 246.2 F g⁻¹ compared to the untreated biochar (115.3 F g⁻¹). The irradiation dose of 100 kGy exhibited higher specific power and specific energy of 0.1 kW kg⁻¹ and 34.2 W h kg⁻¹ respectively, with a capacity retention of above 96% after 10 000 cycles at a current density of 2 A g⁻¹. This improvement can be attributed to the decrease in average particle size, an increase in the porosity of biochar carbon. Besides, the charge transfer resistance of supercapacitor is significantly reduced from 21.7 Ω to 7.4 Ω after treating the biochar carbon with 100 kGy gamma radiation, which implies an increase in conductivity. This gamma radiation strategy to pretreat the carbon material for improving the properties of carbon materials can be promising for the development of high-performance supercapacitors for large-scale applications.

(a) Schematic of the biochar carbon YP-50 exposed to gamma radiation. (b) Cyclic Voltammetry of supercapacitor with untreated biochar and biochar treated with 50 kGy, 100 kGy, and 150 kGy gamma-radiation.     

Portal vein variations in 1000 patients: surgical and radiological importance

Objective:

The purpose of the study was to evaluate the spectrum and incidence of intrahepatic portal vein (PV) variations on triphasic abdomen multidetector CT (MDCT) and to discuss the surgical and radiological implications.

Methods:

A retrospective review of 1000 triphasic MDCT abdomen scans was performed in patients sent for various liver and other abdominal pathologies between January 2014 and August 2014. A total of 967 patients (N = 967) were included in the study. The variations in branching pattern of PV were classified according to classification used by Covey et al (Covey AM, Brody LA, Getrajdman GI, Sofocleous CT, Brown KT. Incidence, patterns, and clinical relevance of variant portal vein anatomy. AJR Am J Roentgenol 2004; 183: 1055–64) and Koç et al (Koç Z, Oğuzkurt L, Ulusan S. Portal vein variations: clinical implications and frequencies in routine abdominal CT. Diagn Interv Radiol 2007; 13: 75–80).

Results:

Normal anatomy (Type I) was seen in 773 patients (79.94%) out of 967 patients in our study. Trifurcation (Type II) anomaly was seen in 66 (6.83%) of cases. Right posterior vein as first branch of main PV (Type III) anomaly was seen in 48 (4.96%) of cases. Type IV anomaly and Type V anomaly was seen in 26 (2.69%) and 13 (1.34%) cases, respectively. 19 cases showed other types of variations.

Conclusion:

Variations in the hepatic PV branching patterns are commonly seen that are similar to variations in hepatic artery and biliary anatomy. Knowledge of these variations is extremely important for transplant surgeons and intervention radiologists.

Advances in knowledge:

Awareness of the variations in PV branching patterns is essential for intervention radiologists and vascular surgeons and avoids major catastrophic events.