Are there any predictive risk factors for failure of ureteric stent in patients with obstructive urolithiasis with sepsis?

Siddharth Pandey,Deepanshu Sharma,Satyanarayan Sankhwar,Manmeet Singh,Gaurav Garg,Ajay Aggarwal,Ashish Sharma,Samarth Agarwal 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.6

Purpose: To compare patients with sepsis due to obstructive urolithiasis (Sep-OU) and underwent drainage by percutaneous nephrostomy (PCN) or a double-J (DJ)-ureteral stent and to identify predictive risk factors of DJ stent failure in these patients. Materials and Methods: We reviewed our records from January 2013 to July 2018 and identified 286 adult patients with Sep-OU out of which 36 had bilateral involvement, thus total 322 renal units were studied. Urologic residents in training carried out both ureteral stenting and PCN tube placement. Demographic data and stone characteristics were recorded along with Charlson comorbidity index. For predicting risk factors of DJ stent failure, those variables that had a p-value <0.1 in univariate analysis were combined in a multinomial regression analysis model. Results: The patients with PCN placement were significantly older than those with DJ stent placement (p=0.001) and also had significant number of units with multiple calculi (p=0.018). PCN was also placed more frequently in those patients with a upper ureteric calculi (p<0.05). On multinomial regression analysis multiple calculi (p=0.014; odds ratio [OR], 4.878; 95% confidence interval [CI], 1.377–17.276) and larger calculi size (p=0.040; OR, 0.974; 95% CI, 0.950–0.999) were the significant predictors of DJ stent failure. Conclusions: In patients with sepsis from obstructive urolithiasis due to larger and multiple calculi a PCN placement might be better suited although this data requires further prospective randomized studies to be extrapolated.

Phase inversion enabled energy scavenger: A multifunctional triboelectric nanogenerator as benzene monitoring system

Khandelwal, Gaurav,Chandrasekhar, Arunkumar,Pandey, Rajagopalan,Maria Joseph Raj, Nirmal Prashanth,Kim, Sang-Jae Elsevier Sequoia 2019 Sensors and actuators. B Chemical Vol.282 No.-

<P><B>Abstract</B></P> <P>Mechanical energy harvesting using Triboelectric nanogenerator (TENG) based on the coupling of electrostatic induction and contact electrification is a cost-effective and straightforward process. TENG is well known for harnessing the waste energy at a large scale. Here, we demonstrated the fabrication of enhanced-performance TENG in contact-separation mode by utilizing the facile phase inversion process for only one triboactive layer. The phase inversion is a straightforward technique to achieve films with a porous structure and high crystallinity. The non-piezoelectric, semiconducting TiO<SUB>2</SUB> microparticle acts as charge trapping sites attributed to their high dielectric constant. The PVDF-10-TiO<SUB>2</SUB>/CA TENG showed 7 times and 10 times enhancement for voltage and short circuit current compared to the PVDF-TiO<SUB>2</SUB>/CA TENG prepared without phase inversion process. Furthermore, the device is a multifunctional energy harvester i.e. it can harvest biomechanical as well as wind energy. Finally, we demonstrated the use of TENG device for volatile organic compounds (VOCs) sensing. The device exhibits good response with the change in concentration as well as total flow rate. The voltage decreases with the increase in the benzene concentration. The sensitivity of as fabricated sensor is 0.0035 V/ppm concerning concentration and 0.29176 V/sccm concerning total flow rate. The sensor was integrated with the Arduino Uno for automatic detection of benzene giving the alarm warning for the presence of benzene in the environment. This work extended the application of TENG in the field of VOCs sensing, design and concept which can be applied in the future for the detection of other VOCs in the environment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Phase inversion and semi conducting TiO<SUB>2</SUB> based TENG with enhanced performance. </LI> <LI> The TENG shows 7 times and 10 times enhancement for voltage and current. </LI> <LI> Fabricated TENG is multifunctional energy harvester. </LI> <LI> Demonstration of TENG as VOC’s sensor with good selectivity and sensitivity. </LI> <LI> Integration of TENG with Arduino for warning message and alarm to evacuate. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Fabrication routes for one-dimensional nanostructures via block copolymers

Tharmavaram Maithri,Rawtani Deepak,Pandey Gaurav 나노기술연구협의회 2017 Nano Convergence Vol.4 No.12

Nanotechnology is the field which deals with fabrication of materials with dimensions in the nanometer range by manipulating atoms and molecules. Various synthesis routes exist for the one, two and three dimensional nanostructures. Recent advancements in nanotechnology have enabled the usage of block copolymers for the synthesis of such nanostructures. Block copolymers are versatile polymers with unique properties and come in many types and shapes. Their properties are highly dependent on the blocks of the copolymers, thus allowing easy tunability of its properties. This review briefly focusses on the use of block copolymers for synthesizing one-dimensional nanostructures especially nanowires, nanorods, nanoribbons and nanofibers. Template based, lithographic, and solution based approaches are common approaches in the synthesis of nanowires, nanorods, nanoribbons, and nanofibers. Synthesis of metal, metal oxides, metal oxalates, polymer, and graphene one dimensional nanostructures using block copolymers have been discussed as well.

Unplanned 30-day readmission rates in patients undergoing endo-urological surgeries for upper urinary tract calculi

Manoj Kumar,Siddharth Pandey,Ajay Aggarwal,Deepanshu Sharma,Gaurav Garg,Samarth Agarwal,Ashish Sharma,Satyanarayan Sankhwar 대한비뇨의학회 2018 Investigative and Clinical Urology Vol.59 No.5

Purpose: To see the 30-day unplanned readmission rates in patients underdoing endo-urological surgeries for upper urinary tract calculi we conducted this retrospective study at King George's Medical University, Lucknow, India. Unplanned readmissions not only add to healthcare costs but also are bothersome for the patients. There are many studies on 30-day unplanned readmissions in general surgical patients. Although similar studies have been done in certain urological procedures, no study has reported readmission rates or its risk factors in patients undergoing surgeries for upper urinary tract calculi. Materials and Methods: We retrospectively reviewed our prospectively maintained database from 1st January 2009 to 31st December 2017, for the patients who underwent endo-urological procedures for upper urinary tract calculi and identified the patients who were re-admitted within 30 days of discharge. Results: Out of the total 3,209 patients undergoing endo-urological procedures for upper urinary tract calculi 56 were re-admitted. The readmission rate was 1.74% over the study period. The most common etiology for readmission was sepsis followed by hematuria. The significant risk factors for readmission in bivariate analysis included male gender, age >65 years, current smoking, chronic obstructive pulmonary disease, diabetes mellitus, bleeding disorder, prior cardiac disease, and American Society of Anesthesiologists (ASA) class ≥3. In multivariate risk adjusted logistic regression analysis ASA class ≥3 was the only independent risk factor for readmission. Conclusions: The readmission rates in endo-urological procedures for urolithiasis are less compared to other procedures. ASA class ≥3 is the most important independent predictor of unplanned 30-day readmissions.

Underwater Image Dehazing via Unpaired Image-to-image Translation

조영근,Hyesu Jang,Ramavtar Malav,Gaurav Pandey,김아영 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.3

Underwater imaging has long been focused on dehazing and color correction to address severe degradation in the water medium. In this paper, we propose a learning-based image restoration method that uses Generative Adversarial Networks (GAN). For network generality and learning flexibility, we constituted unpaired image translation frameworks into image restoration. The proposed method utilizes multiple cyclic consistency losses that capture image characteristics and details of underwater images. To prepare unpaired images of clean and degraded scenes, we collected images from Flickr and filtered out false images using image characteristics. For validation, we extensively evaluated the proposed network on simulated and real underwater hazy images. Also, we tested our method on conventional computer vision algorithms, such as the level of edges and feature matching results.