Novel Dual Band Frequency Selective Surface and its Applications on the Gain Improvements of Compact UWB Monopole Antenna

In this work, a highly directional ultra-wideband (UWB) microstrip patch antenna as a single-element is suggested. The proposed antenna’s gain is enhanced with a novel dual-band frequency selective surface (FSS) placed beneath it. The FSS design has a hexagonal structure with meander line inductances and a capacitance-like structure connecting all of the corners to the middle. There is no metallic layer on the other side of the substrate, which shows transmission zeros at 4.95 GHz and 12.7 GHz, and a modified U-shaped monopole antenna is developed. First, the performance characteristics of the antenna and FSS are analyzed from the simulation results, and they are validated experimentally after fabrication, followed by measurement. The compact configuration comprises an antenna loaded with the proposed FSS results S11 less than -10 dB from 3.15 GHz to 22.65 GHz, covering the UWB band together with the X, Ku-band with a bandwidth of 19.5 GHz (151.16% FBW). The antenna’s overall physical dimensions would be 38.8 mm×38.8 mm×25.2 mm (0.407λo×0.407λo×0.265λo), with λo denoting the lowest frequency’s free-space wavelength. The FSS loading results in a 9.9 dBi maximum gain at 10 GHz. The antenna’s small size increases bandwidth, and its high peak gain makes it ideal for use in real-time applications

Compact UWB Monopole Antenna with Tunable Dual Band Notched Characteristics for WiMAX and WLAN Applications

The present work shows a planar compact ultra-wideband (UWB) monopole antenna with controllable dualband-notch frequencies at 3.3 GHz for WiMAX and 5 GHz for WLAN. In the proposed antenna, the lower notchband (at a frequency of 3.3 GHz) is made by cutting a thin horizontal strip on top of the radiating patch. The uppernotch band (at a frequency of 5 GHz) is made by putting two narrow parasitic strips in the shape of an “I” oneither side of the radiating patch. The incorporation of three varactor diodes between the radiating patch and three metallic strips provides the flexibility of adjusting the notch frequencies. The notch band tunability between 3.15 GHz and 3.69 GHz and between 4.93 GHz and 5.59 GHz, respectively, is achieved by changing the bias voltageof the varactor diode between 0 V and 30 V. The gain and efficiency characteristics of the designed antenna alsoexhibit band rejection at the respective notch frequencies. The design principle is validated by fabricating andmeasuring a prototype of the proposed dual-band, notched UWB antenna. For three different bias voltages of thevaractor, the simulated and experimental findings are in reasonable agreement. The proposed works demonstratebetter-notch characteristics as compared with other reported works over the UWB rang

Infected gap nonunion of fractures proximal humerus in adolescent: an outcome of 12 cases

Background: There is little data about the risk factors, demographics, and prognosis for nonunions in children. Previous literature has reviewed time periods when contemporary techniques of internal fixation and management of open injuries had not been available. Infected gap nonunion of proximal 1/3 humerus in adolescent is not much reported the in literature. The purpose of our study was to evaluate the outcome of infected gap nonunion in 12 cases of adolescent treated by debridement and fibular graft and plating.Methods: This study was conducted between 2009 to 2015, 12 cases of Infected gap nonunion of fractures proximal humerus was included in our study. Each child was followed up minimum for 12 months.  Although non unions in the pediatric population are rare, these data underscore the importance of careful evaluation and treatment of these fractures at risk for nonunion.Results: In our series of 12 cases of infected nonunion of fracture humerus which were treated by bone grafting using fibula strut graft and plating resulted 99% union rate. The rate of union is depending on thorough debridement and fixation along with bone grafting.Conclusions: Nonunion of pediatric fractures is a rare complication. Most studies on developing pediatric nonunions describe specific fractures that are particularly susceptible to nonunion and malunion, nonunion of humeral lateral condyle and open tibia fractures have received the most attention. Reports of nonunion among pediatric long bone fractures are rare, being either case reports or isolated entities in a larger series of predominantly adult fractures. Fibula is a popular substitute for this method because of its easy accessibility and minimal donor site morbidity

Laryngeal Neuroendocrine Tumor - An Atypical Presentation

Neuroendocrine tumors of the larynx are the most common non-epidermoid tumors of the larynx and comprise less than 1% of the laryngeal tumors. Most of the symptoms and presentation mimic any usual laryngeal malignancy making the diagnosis difficult. Here, we report a case of laryngeal neuroendocrine carcinoma that was managed with total laryngectomy

Some aspects of animal behavior and community dynamics

We simulate the dynamical behavior of a few two - dimensional predator - prey systems in two - dimensional parameter spaces to gain insight into how functional responses affect community dynamics. The insight gained helps us design three dimensional systems. We construct models for a few ecosystems with three species and study them using computer simulations. The models have been developed by linking food chains which have both kinds of predators: specialist as well as generalist. The linking functions are weakly non-linear. The three dimensional model ecosystems have sexually reproducing top - predators. We perform extensive simulations to figure out dynamics of dynamical possibilities caused by changes in animal behavior. The animals change the foraging strategies and behave differently in different environments. At the end of the paper, we examine how diseases can govern transitions in meandering of dynamical models in bounded volume of their phase spaces

EFFECTS OF INTRATHECAL MIDAZOLAM IN SPINAL ANAESTHESIA: A PROSPECTIVE DOUBLE BLINDED CASE CONTROL STUDY

Background: Increasing the duration of action and maximizing postoperative analgesia has always been a domain of interest in spinal blocks. Many adjuvants have been tried along with local anaesthetic agent to achieve the same. The following study was conducted to compare sensory and motor characteristics with 2mg midazolam in subarachnoid block. Aim: To evaluate the efficacy and analgesic effect of the mixture of 2 mg midazolam and 15 mg (3 ml) hyperbaric bupivacaine as compared to bupivacaine alone in patients undergoing infra-umbilical surgery under spinal block. Material and Methods: In this observational prospective case control study 100 patients (ASA class I and II), aged 18 to 55 years, undergoing elective infra-umbilical surgeries under spinal block were randomly divided into Group I- patients were administered 0.5% hyperbaric Bupivacaine (3 ml) + 0.9% Normal saline (0.4 ml) intrathecally and Group 2- patients were administered 0.5% hyperbaric Bupivacaine (3 ml) + 2mg preservative free Midazolam (0.4 ml) intrathecally. The onset and duration of sensory and motor block, hemodynamic variables, and side effects during the surgery and recovery were compared among the groups. Results: 2mg of preservative free midazolam used as an adjuvant to bupivacaine intrathecally reduces onset time of sensory and motor blockade, also time taken to reach T-10. It also increases time taken for two segmental recession and mean duration of analgesia. Conclusion: It can be inferred that Inj. Midazolam 2 mg in combination with Inj. bupivacaine  0.5% hyperbaric can be safely administered  intrathecally for better postoperative analgesia. KEYWORDS: Intrathecal Midazolam; Post-operative Analgesia; Bupivacaine; Spinal Anesthesia

EFFECTS OF INTRATHECAL MIDAZOLAM IN SPINAL ANAESTHESIA: A PROSPECTIVE DOUBLE BLINDED CASE CONTROL STUDY

Background: Increasing the duration of action and maximizing postoperative analgesia has always been a domain of interest in spinal blocks. Many adjuvants have been tried along with local anaesthetic agent to achieve the same. The following study was conducted to compare sensory and motor characteristics with 2mg midazolam in subarachnoid block. Aim: To evaluate the efficacy and analgesic effect of the mixture of 2 mg midazolam and 15 mg (3 ml) hyperbaric bupivacaine as compared to bupivacaine alone in patients undergoing infra-umbilical surgery under spinal block. Material and Methods: In this observational prospective case control study 100 patients (ASA class I and II), aged 18 to 55 years, undergoing elective infra-umbilical surgeries under spinal block were randomly divided into Group I- patients were administered 0.5% hyperbaric Bupivacaine (3 ml) + 0.9% Normal saline (0.4 ml) intrathecally and Group 2- patients were administered 0.5% hyperbaric Bupivacaine (3 ml) + 2mg preservative free Midazolam (0.4 ml) intrathecally. The onset and duration of sensory and motor block, hemodynamic variables, and side effects during the surgery and recovery were compared among the groups. Results: 2mg of preservative free midazolam used as an adjuvant to bupivacaine intrathecally reduces onset time of sensory and motor blockade, also time taken to reach T-10. It also increases time taken for two segmental recession and mean duration of analgesia. Conclusion: It can be inferred that Inj. Midazolam 2 mg in combination with Inj. bupivacaine  0.5% hyperbaric can be safely administered  intrathecally for better postoperative analgesia. KEYWORDS: Intrathecal Midazolam; Post-operative Analgesia; Bupivacaine; Spinal Anesthesia

Fracture neck of femur treated with hemiarthroplasty and cannulated cancellous screw fixation: a comparative study

Background: Intracapsular fracture neck of femur has always presented great challenges to every Orthopaedic surgeons and it is remain a mystery whether to fix or to replace the fracture in the elderly. The aim of the study was to analyze the functional outcome of two widely used and accepted modalities of treatment in the age group 57-75 years, in Garden’s type I and II fractures, namely (a) cannulated cancellous screw fixation(internal fixation) and (b) modular bipolar prosthetic replacement of the femoral head (hemiarthroplasty).Methods: The total 110 patients were including in the study from age groups 57-75 (mean age 66). The Garden classification of fracture neck of femur was used to evaluate the displacement of femoral neck fractures. Only grade 1 and 2 was included in the study. 55 patients were included in each group A and B. Osteosynthesis (fracture fixation) was carried out by closed reduction and insertion of cannulated cancellous screw and in other group hemiarthroplasty was done.Results: In group A 55 patient with fracture neck of femur was treated by osteosynthesis i.e. fixation using 02 or 03 cannulated cancellous screw and in group B, 55 patients with fracture neck of femur was treated by modular bipolar replacement hemiarthroplasty. In Group A out of 55, 41 patients union was achieved between 08 to 14 months (mean 11.5 month), 09 patients developed non-union even after 16 months and 05 patients develop collapse of head with AVN with shortening at end of 02 year, however in Group B out of 55 patients 51 patients started walking after 2nd postoperative days, 02 patients developed infection, and 02 patients developed posterior dislocation.Conclusions: The fracture fixation may be tempting for fracture neck femur in age group 57-75 especially of Garden Type I but internal fixation put risk of non-union and AVN and second surgery may be required after few months or years  if patients survive. Based on results in our study we therefore can conclude that in Garden Type I and II femur neck fractures in the patients between 57-75 years of age, hemiarthroplasty is the better modality of treatment