bluuebunny/crossref_metadata_2025 huggingface dataset:
Separation of Multiple Speech Signals by usingTriangular Microphone Array
Authors: Hamada Nozomu
Published: March 2022

Speech source separation has been an important topic to realize speech-based human-machine interfaces or high quality hand-free communication with machines. For source separation, Independent Component Analysis (ICA) and time-frequency masking are powerful methods as a tool of Blind Source Separation (BSS) of speech mixtures. The latter method is based on the assumption called \W-Disjoint Orthogonality" which implies the cell component sparsity of speech in the time-frequency domain. One of the topics treated in this article is to introduce the time-frequency masking scheme is applied to the equilateral triangular array where the three delay estimates from each microphone pairs are obtained. In addition, it is used to improve histogram-mapping algorithm by integrate and coordinate transformation of three delay estimates. Some experiments in real environment for separating multiple sources are performed to verify the effectiveness.
A 0.5 - 5.5 GHz Distributed Low Noise Amplifier
Authors: Lourandakis Errikos , Plessas Fotis , Kalivas Grigorios
Published: March 2022

The Low Noise Ampli¯er (LNA) presented in this work is a 3-stage fully integrated Distributed Amplifier (DA) using a 0.35 ¹m BiCMOS SiGe process. The circuit was designed for integration and for this reason the di®erent parasitical phenomena that concern the spiral inductors and the packaging were evaluated in detail. Noise Figure (NF) and linearity were also investigated through simulations. The designed amplifier offers a gain of about 7 dB with a gain flatness of 0.6 dB over the bandwidth 0.5-5.5 GHz and an average noise ¯gure of 3.2 dB. The RF input port is matched to 50 ­, with worst-case return loss of 10 dB over the whole bandwidth. The input-referred P1dB point varies from 2.2 dBm at 1 GHz to 3.1 dBm at 5 GHz. Within the same bandwidth the IP3 varies from 6 dBm to 13.3 dBm. The estimated power consumption is 82.5 mW from a 3V power supply.
Proposal for Simple Repetitive Controllers
Authors: Yamada Kou , Takenaga Hiroshi , Saitou Yusuke , Satoh Keiji
Published: March 2022

The modified repetitive control system is a type of servomechanism for periodic reference input. Even if the plant does not include a time delay, the transfer functions from both the reference input and the disturbance of the output of the modi¯ed repetitive control system generally have an in¯nite number of poles, and for this reason it is di±cult to settle the input-output and the disturbance attenuation characteristics of a modi¯ed repetitive control system. From a practical point of view, the input{output and the disturbance attenuation characteristics of a control system need to be settled easily, and thus, it is desirable that the transfer functions from both the reference input and the disturbance to the output have a finite number of poles. In order to easily specify the input-output and the disturbance attenuation characteristics, we propose the concept of a simple repetitive control system in which the controller works as a stabilizing modi¯ed repetitive controller and the transfer functions to the output from both the reference input and the disturbance have a ¯nite number of poles. In addition, the parametrization of all stabilizing simple repetitive controllers is clarified. A simple design procedure for a stabilizing simple repetitive controller is presented.
Adaptive Window Length Recursive Weighted Median Filter for Removing Impulse Noise in Images with details Preservation
Authors: Kumar V.R.Vijay , Manikandan S. , Vanathi P.T. , Kanagasabapathy P. , Ebenezer D.
Published: March 2022

An adaptive window length Recursive Weighted Median filter [ARWMF] for removing the impulse noise with better edge and ¯ne detail preservation is presented. Larger window size may blur the images and the lower window size does not remove the noise at high density. To overcome this, the window size of the RWMF is adaptive based on the presence of noise density. Median controlled algorithm is used to calculate the weights for the RWMF. In median controlled algorithm, the ¯lter gives the smallest weight for the impulse. However, for many weight functions, including the exponential one, this weight is non-zero. Thus the impulse has an effect on the output and the magnitude of the impulse is reduced. The computational complexity for the weight calculation is simple and it is very efficient. The window size of the RWMF is adaptive based on the presence of noise density. The proposed algorithm produces better edge and fine details preservations and reduces blurring at the high density impulse noise.The performance of the proposed algorithm is given in terms of mean square error (MSE), mean absolute error (MAE) and peak signal to noise ratio (PSNR) and it is compared with Standard Median ¯lters, Weighted Median filters, Center Weighted Median ¯lters, Recursive Weighted Median filters and Lins Adaptive length Recursive weighted median filters using Median Controlled Algorithm.
Network and Embedded Applications of Automatic Speech Recognition
Authors: Hataoka Nobuo , Kokubo Hiroaki , Lee Akinobu , Kawahara Tatsuya , Shikano Kiyohiro
Published: March 2022

ASR (Automatic Speech Recognition) is one of key technologies in the upcoming Ubiquitous Computing and Ambient Intelligence. In this paper, first, the surveys on processing devices such as microprocessors and memories, and on communication infrastructure, especially wireless communication infrastructure relating to ASR are reported. Second, the embedded version of CSR (Continuous Speech Recognition) software for the mobile environmental use of ASR is reported. As the devices, RISC based microprocessors, semiconductor memories, and HDD are summarized. For the communication infrastructure, mobile communications and wireless LANs are described. Finally, implementation results of the free CSR software called Julius on the T-engineTM consisting of an SH-4A mi-croprocessor are reported.
Robust H State-Feedback Control Design for Nonlinear Time-Varying Delay Systems Based on An LMI Approach
Authors: Assawinchaichote Wudhichai
Published: March 2022

This paper examines the problem of designing a robust H state-feedback controller for a class of nonlinear systems with time-varying delay described by a Takagi-Sugeno (TS) fuzzy model. Based on a linear matrix inequality (LMI) approach, we develop a robust H state-feedback controller which guarantees the L2-gain of the mapping from the exogenous input noise to the regulated output to be less than some prescribed value for this class of nonlinear systems. A numerical example is provided to illustrate the design developed in this paper.
Low-Temperature Micro-PL Measurements of InAs Binary Quantum Dots on GaAs Substrate
Authors: Chit Swe Nan Thidar , Suraprapapich Suwaree , Wissawinthanon Chanin , Panyakeow Somsak , Tu Charles W. , Arakawa Yasuhiko
Published: March 2022

Optical properties of InAs binary quantum dot (bi-QD) molecules grown on the (001) GaAs substrate were measured by means of temperature- and excitation-power-dependent photoluminescence (PL) spectroscopy. It was observed that the shape and peak position of the PL spectra changed with the temperature and with the excitation power. It was also found that the linear polarization degree of the bi-QD PL signal changed with temperature. The temperature-dependent PL described that the linear polarization degree of bi-QDs is closely related to the carrier dynamics.
Compact FPU Design and Embedding in a Ubiquitous Processor for Multimedia Performance Enhancement
Authors: Fukase Masa-aki , Sato Tomoaki
Published: March 2022

The key to protect huge amount of multimedia data in ubiquitous networks is to introduce safety aware high-performed single VLSI processor systems embedded with cipher process. Thus, we exploited the architecture of a hardware cryptography embedded multimedia mobile processor named HC-gorilla by sophisticatedly unifying up-to-date processor techniques. Although it was provided with carefully selected Java bytecodes and cipher codes, FP (floating point) expression was omitted due to the restriction of hardware resource. Considering recent trend of embedded applications like voice recognition, 3D graphics, and image/vision processing, FP hardware is crucial for further enhancing HCgorillafs Java functions. We focus in this article the development of a compact FPU (Floating point number Processing Unit). A compact FP format speci¯c for HCgorilla is IEEE 754 compatible except the bit width representation of FP data. Prioritizing the latency of FPU, it has only 5 stages. The compact FPU is built in HCgorilla by adding 16 FP arithmetic codes and improving the decode stage of the previous HCgorilla. By using a 0.18-¹m standard cell CMOS technology supported by VDEC, we have so far accomplished the logic synthesis and behavior simulation. The 400MHz of clock frequency is justified from delay analysis.
MPTCP: How Can Route Diversity Improve the Internet Traffic?
Authors: Melakessou Foued , Sorger Ulrich , Suchanecki Zdzislaw
Published: March 2022

This contribution aims to provide the fundamental basis of a new Transmission Control Protocol (TCP) designed for the next generation Internet. The TCP protocol is not capable to carry out all the growing traffic generated by the Internet as it leads to congestion and packet loss out of the quality of service specially required for critical connections. Moreover this behavior is accentuated in heavy load conditions. The Internet traffic becomes bursty and this trend is amplified as more participants contribute to generate data connections on a shared complex infrastructure. Therefore we focus on the design of a new protocol that aims to avoid or partially reduce the congestion appearance and the high variability of the Internet traffic. The stationarity of connection paths met on the Internet are judged responsible of the emergence of these characteristics. As a consequence a TCP-like protocol based on Multiple Paths (MPTCP) is suggested for a data transmission between two network entities in order to improve the QoS of the de¯ned connection. We propose there several algorithms that aim to extract multiple routes between two network components. This work is based on a theoretical modeling supported by simulations. Our network simulator is developed on top of the Scilab environment.
Fast Algorithms for Computing Parsimonious Estimates of QoS Measures
Authors: Biro Jozsef
Published: March 2022

In recent publications concerning quality of service (QoS) measures in communication networks several attempts have been made to improve the techniques of computing or estimating the quality of data transfer. Many of the promising results are based on the knowledge of only very few parameters on the traffic situation, some of which are known a priory, others are measured. The paper deals with such parsimonious estimation techniques of QoS measures under the bufferless fluid flow multiplexing (bffm) framework, and concentrates on the efficient computation of them. The proposed fixed-point recursive algorithms are key elements in applying either the implicit formulae or ones containing optimization tasks in real-time environment.
A Simple and Accurate Formula for Oscillating Amplitude of CMOS LC Differential Oscillator
Authors: Hen- ngam Nikorn , Mahatanakul Jirayuth
Published: March 2022

The conventional formula for the oscillation amplitude of the CMOS LC differential oscillator was derived under the assumption that the current from sourced coupled pair flowing though LC tank is a square wave. This is not in line with the real situation and the obtained formula is independent of the MOSFET parameters. In this paper, aderivation of a simple and accurate expression for oscillating amplitude of CMOS LC differential oscillator in which the current from sourced coupled pair is assumed to be clipped sinusoid is presented. By comparing to the simulation results, it was found that the new expression of oscillating amplitude is more accurate than the widely used conventional expression.
Criterion of Approximation for Designing 2 × 2 Feedback Systems with Inputs Satisfying Bounding Conditions
Authors: Chuman Tadchanon , Arunsawatwong Suchin
Published: March 2022

A common practice in designing a feedback system with a non-rational transfer matrix is to replace the non-rational matrix with an appropriate rational approximant during the design process so that reliable and effcient computational tools for rational systems can be utilized. Consequently, a criterion of approximation is required to ensure that the controller obtained from the approximant still provides satisfactory results for the original system. This paper derives such a criterion for the case of two-input two-output feedback systems in which the design objective is to ensure that the errors and the controller outputs always stay within prescribed bounds whenever the inputs satisfy certain bounding conditions. For a given rational approximant matrix, the criterion is expressed as a set of inequalities that can be solved in practice. It will be seen that the criterion generalizes a known result for single-input single-output systems. Finally, a controller for a binary distillation column is designed by using the criterion in conjunction with the method of inequalities.
The Simplified Control of Three-Phase Four-Leg Shunt Active Power Filter for Harmonics Mitigation, Load Balancing and Reactive Power Compensation
Authors: Po-Ngam Sakorn
Published: March 2022

In this paper, the simplified control of three-phase four-leg shunt active power filter for harmonics mitigation, load balancing and reactive power compensation is proposed. In order to calculate the harmonics, current imbalance and reactive power, the load currents are detected and transformed to dq0 variables. By using the low-pass filter, the fundamental active power current can be separated from the d-axis current. Therefore, the commanded active power filter currents are consist of d-axis harmonic currents, q-axis and 0-axis currents. These components are regulated by the PI controller with feedforward utility voltage via the four-leg space vector inverter. Moreover, the design guidelines of space vector phase-locked loop (PLL), current controllers and DC-bus voltage controller are also presented. Validity of the proposed control schemes is confirmed by the simulation.
Reduced-Nonlinear Effect on Magnetic Recording Channels Using MMSE Equalizers
Authors: Sirirungsakulwong A. , Puttarak N. , Supnithi P.
Published: March 2022

This paper considers the nonlinear effect on magnetic recording channels in order to reduce the system distortion. In this work, we propose the designed MMSE equalizer and target for a high density perpendicular magnetic recording to combat the nonlinear transition shift (NLTS) in a channel characterized by jitter noise and additive white Gaussian noise (AWGN). Due to a complex nature of nonlinear effects, the nonlinearity of a read-back signal is designed by the second order Volterra model consisting of linear and nonlinear part. The bit-error rate (BER) of the nonlinear-affected system using the designed MMSE equalizer is significantly decreased. The results show that the proposed minimum mean square error (MMSE) equalizer with  constraint can decrease the inter-symbol interference (ISI) that causes nonlinearity and also improve performance.
Impact of Strain on Fully Depleted Strained Gate Stack Double Gate MOSFET: A Simulation Study
Authors: Pradhan K. P. , Mohapatra S. K. , Sahu P. K , Parija S.
Published: March 2022

The fusion of strain engineering and multigate technology is implemented to design an advanced MOSFET model i.e. Fully Depleted Strained Gate Stack Double Gate (FD-S-GS-DG) in nanoscale regime. Both DC and Analog performances of FD-S-GS-DG are analyzed by varying the Ge mole fraction (X). The sensitivity of crucial device parameters like threshold voltage (Vth), subthreshold swing (SS), on-current (Ion), off state leakage current (Ioff), on-off ratio (Ion/Ioff), transconductance (gm), output conductance (gd), early voltage (VEA), gain (AV), transconductance generation factor (TGF) towards X are successfully evaluated and presented. From the obtained results, by considering appropriate value of X, one can enhance the device performance by an immense aspect.
Performance Improvement of ACO-OFDM Indoor Optical Wireless Transmissions Using Partial Pre-Equalization
Authors: Panta Jariya , Saengudomlert Poompat , Sripimanwat Keattisak
Published: March 2022

This paper analyzes the performances and presents the benets of partial pre-equalization for indoor optical wireless transmissions based on asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM) with intensity modulation and direct detection (IM/DD). In particular, for diffuse indoor optical wireless channels, partial pre-equalization can reduce the optical transmit power over post-equalization at the same target bit error rate (BER) for point-to-point transmissions even with imperfect channel knowledge. To further im-prove its performance, bit loading is considered to minimize the optical transmit power of ACO-OFDM while maintaining a constant target BER. In addition, broadcast transmissions to multiple users with possibly dierent channel qualities are considered, where pre-equalization is not applicable. Finally, we specify an appropriate channel estimate at the transmitter for such broadcast transmissions.
Adaptive Two-stage Spectrum Sensing under Noise Uncertainty in Cognitive Radio Networks
Authors: Lee Wilaiporn , Thakulsukanant Kornkamol , Srisomboon Kanabadee , Prayote Akara
Published: March 2022

To utilize licensed spectrum bands efficiently, spectrum sensing needs to be accurate and fast. The occurrence of noise uncertainty and the lower in received PU signal power due to the distance between the transmitter and the receiver, path loss, are the main challenges that has a great impact on the accuracy of spectrum sensing.
In this paper, we propose a new scheme of two-stage spectrum sensing, “Adaptive Two-stage Spectrum Sensing (ATSS)”, under noise uncertainty environment. ATSS is a modified of a conventional two-stage spectrum sensing where the decision threshold of both stages are adapted on the distance, estimated noise variance and calculated noise uncertainty interval. Therefore, ATSS improves the detection performance of the existing spectrum sensing and is robust to noise uncertainty.
The contribution of this paper is three-fold. First, an unreliable detection and wasted stage activation of a conventional two-stage spectrum sensing are reduced. Second, noise uncertainty is addressed. Third, a new parameter, critical distance ( ), is proposed in order to reduce computational burden and sensing time of the first stage.
Policies for Channel Allocation in Cognitive Radio Networks using Game Theory
Authors: Bhattarai Amulya , Charoenlarpnopparut Chalie , Suksompong Prapun , Komolkiti Patrachart
Published: March 2022

Cognitive radio networks evolve according to the actions of selsh users who act independently. The eventual state reached in most of the cases by such a system is a Nash Equilibrium (NE). Multiple NE with dierent quality may exist. In this work we consider the problem of allocating channels to multiple transceivers. Based on policies derived from various network metrics we develop a way to initialize the allocation and choose the appropriate channel for each user to push the system towards a higher normalized cumulative total throughput of the CRN. A novel equation to allocate channels is also derived. The improvement is conrmed by our simulation results.
Energy Storage System Sizing for Peak Shaving in Thailand
Authors: Dejvises Jackravut
Published: March 2022

This paper presents a mathematical model of energy storage systems (ESSs) to minimise daily electrical peak power demand in Thailand. A daily electrical load curve on a peak day obtained from Electricity Generating Authority of Thailand (EGAT) is used to analyse the capability of energy storage system for electrical peak power demand reduction with different ESS sizes. It is found that with power rate of 50 percent of the difference between the minimum and the maximum demands of the daily load curve and with energy capacity of 50 percent of the sum of each time step absolute energy difference between the demand and the average demand of the daily load curve, ESS can decrease daily electrical peak demand approximately 7.4 percent and increase daily load factor approximately 9.9 percent.
Optimal Siting of UPFC on a Transmission Line with the Aim of Better Damping of Low Frequency Oscillations
Authors: Gholizadeh-Roshanagh Reza , Mohammadzadeh Behrouz , Najafi-Ravadanegh Sajad
Published: March 2022

Low frequency oscillations may cause blackouts. Power system operators are increasingly facing instability problems due to the fact that the current system is much more loaded than before. Tuning the lead-lag controllers, as power system stabilizers (PSS) or FACTS-based supplementary stabilizers, is a well-established method to enhance the damping capability of power systems. In this paper we propose a technique to optimally locate the place of unified power flow controller (UPFC) on a transmission line considering low frequency oscillation (LFO) damping. The proposed method is applied to a single machine infinite bus system equipped with UPFC and the results obtained show its superiority.
Micro-slotted Dual-stage Spectrum Sensing for Cognitive radio networks
Authors: Lee Wilaiporn , Srisomboon Kanabadee , Thakulsukanant Kornkamol , Prayote Akara
Published: March 2022

Spectrum sensing is used to determine an existence of a primary user in order to avoid harmful interference to the primary user caused by a secondary user in cognitive radio network. In general sensing, a PU is assumed to use the band since the beginning of the sensing period. In fact, a PU can be active at any time of the sensing period.
In this paper, we propose a novel technique — micro-slotted dual-stage spectrum sensing (MDMS) — to detect a PU no matter when it is active during the sensing period. The technique also addresses low SNR due to path loss effect in an adaptive fashion. The technique is more reliable compared to previous works of MDCAED and DCAED. MDMS is shown that it meets the spectrum sensing requirement (IEEE 802.22) of sensing time for all distances and gives the best detection performance among the other techniques. Not only the primary user can be ensured that its transmission will not be interfered by the secondary user, the number of detecting spectrum bands by the SU also increases because it consumes short sensing time. Thus, the efficiency of spectrum utilization can be improved.
A Nonisolated Bidirectional ZVS Converter for Low Power Application
Authors: Vesali Mahmood , Delshad Majid
Published: March 2022

In this paper, a new zero voltage switching bidirectional DC-DC converter with low number elements is proposed. The synchronous rectification and soft-switching techniques are adopted to reduce the conduction loss and switching loss respectively. In the proposed converter any auxiliary circuits for providing soft switching conditions are not used, therefore the efficiency can be improved. In this converter the switches are gated with PWM signal and in complementary form, therefore the implementation of control circuit is simple. Since the proposed bidirectional DC-DC converter has only three main components with two snubber capacitors, the power density is very high. Simulation and experimental results verified the theoretical analysis and the efficiency of proposed converter in full load is about 96%.
Experimental Study in Error Vector Magnitude of Bidirectional Confidential with Median Filter on Spatial Domain Optical Flow under Non Gaussian Noise Contamination
Authors: Kesrarat Darun , Patanavijit Vorapoj
Published: March 2022

In this paper, we focus on the robustness in noise tolerance of spatial domain optical flow and we present a performance study of bidirectional confidential with median filter on spatial domain optical flow (spatial correlation, local based, and global based) under non Gaussian noise where several noise tolerance models on spatial domain optical flow are used in comparison. The experiment results are investigated on robustness under noisy condition by using non Gaussian noise (Poisson Noise, Salt & Pepper noise, and Speckle Noise) in contamination with several standard sequences. The experiment concentrates on Error Vector Magnitude (EVM) as a performance indicator where the result in motion vector (MV) of each method is used to compare with the ground truth vector in the experimental performance analysis.
Performance Comparison of a Second-order adaptive IIR Notch Filter based on Plain Gradient Algorithm
Authors: Loedwassana Wuthiporn
Published: March 2022

This paper presents performance analysis of a second-order adaptive IIR notch filter with constrained poles and zeros in direct form II structure that is adapted by algorithms of indirect and direct frequency estimations based on plain gradient. In this work, the steady-state bias properties and stability bounds of both algorithms are derived in closed form. The simulated processes are performed in order to verify the analytical results. Furthermore, these results of the proposed filter are also compared with those results of the direct form I adaptive IIR notch filter under the same parameters. It has been revealed that the direct form II structure has given the steady-state performance over the direct form I structure.
A modified-SAW for network selection in heterogeneous wireless networks
Authors: Bendaoud Fayssal
Published: March 2022

In the context of heterogeneous networks, users with multi-mode terminals can connect to different radio access technologies such as 802.16, 802.11, HSPA and LTE at the same time. The challenge here is to achieve the Always Best Connected ABC concept; the main issue is the automatic choice of the suitable Radio Access Technology RAT from the list of the available RATs. This decision is called the network selection. In this paper, we propose a modified-SAW function to deal with the drawbacks of the existing solutions. Indeed, the existing MADMs methods suffer mainly from the famous problem of rank reversal once an alternative is added or removed, other problems occur in the legacy MADMs such as the sensitiveness to the user preference in TOPSIS; the penalization of the alternatives with poor attributes values in WPM. Our simulations brought out the lakes of the traditional MADMs approach in the context of network selection. We modify the SAW method intelligently and we use it to solve the network selection problem. Finally, we compare the performance of our solution with the previous works in different scenarios; the simulations show that our proposal outperforms the other existing methods.
Sum-Rate Upper Bounds for the Gaussian X Channel with Limited Receiver Cooperation
Authors: Tan-a-ram Surapol , Benjapolkul Watit
Published: March 2022

In this paper, we propose sum-rate upper bounds in terms of the sum of 3 rates and the sum of 4 rates for the two-user Gaussian X channel with limited receiver cooperation. These upper bounds are derived by using the Fano's inequality, the data processing inequality and genie-aided techniques. Then, we explore the generalized degrees of freedom (GDoF) of the proposed upper bounds with a symmetric channel setting. By setting a certain set of parameters, the received results show that our results are identical to the existing results for both non-cooperation and limited receiver cooperation cases. Moreover, we obtain that the GDoF computed from our proposedupper bounds are greater than the GDoF of those in the non-cooperation case.
Fair Route Selection in Multi-Domain WSNs using Non-Cooperative Game Theory in Separate Sink Scenario
Authors: Singsanga Sajee , Usaha Wipawee
Published: March 2022

An important use of multi-domain wireless sensor networks (WSNs) is resource sharing between different networks co-existing in the same area to prolong the network lifetime. The challenge of resource allocation in such scenario is how to determine packet forwarding strategies which are beneficial to all networks under constrained resources in non-cooperative multi-domain WSNs. Therefore, this paper proposes the Non-cooperative game algorithm based on Lemke Howson method (NCG-LH) for a packet forwarding game in non-cooperative multi-domain WSNs. The objective is to achieve the best mutual strategy and improve the network performance between two different network authorities in non-cooperative multi-domain WSNs in separate sink scenario. Results show that NCG-LH can obtain longer network lifetime than the existing routing algorithms particularly in presence of failed nodes and high path loss. NCG-LH also outperforms the other routing algorithms in terms of fair route selection by attaining the lowest average difference in energy consumption.
Pengetahuan dan Sikap Masyarakat terhadap Penggunaan Styrofoam sebagai Wadah Makanan
Authors: Maulida Setiawan Meutia , Suparni Suparni , Asih Tri Nurhayati
Published: March 2022

Styrofoam adalah material dari polytrene kemasan yang umumnya berwarna putih dan kaku yang sering digunakan sebagai kotak pembungkus makanan. Styrofoam dijadikan wadah makanan karena murah, mudah didapat, tidak mudah rusak, tidak perlu dibersihkan, dan dapat langsung dibuang ketika sudah tidak digunakan. Akan tetapi Styrofoam berbahaya bagi kesehatan dan lingkungan. Tujuan penulisan literatur review ini untuk mengetahui hubungan pengetahuan dan sikap masyarakat terhadap penggunaan Styrofoam sebagai wadah makanan. Metode yang digunakan adalah literatur review dengan mencari sumber informasi melalui database secara online didapatkan sebanyak 271 jurnal dari tiga database kemudian di screening sehingga didapatkan 9 artikel jurnal yang terdiri dari jurnal nasional dan jurnal internasional yang dapat dianalisis sesuai dengan topik yang diangkat. Berdasarkan hasil literatur didapatkan bahwa pengetahuan dan sikap masyarakat berhubungan dengan penggunaan Styrofoam sebagai wadah makanan.
SARS-CoV-2 Reverse Transcription-Polymerase Chain Reaction Positivity and Seroprevalence among Health Care Workers in a Referral Cancer Institute: A Cross-sectional Study
Authors: Zekri Abdel-Rahman , Ahmed Ola S. , Asem Noha , Musa Sherief , Ibrahem Mohamed , Soliman Hany K. , Hafez Mohammed M. , Nessim Margrit S. , Aboelkasem Hatem , Bahnassy Abeer A.
Published: March 2022

BACKGROUND: During the ongoing coronavirus disease 2019 pandemic, healthcare workers (HCWs) are presumed to be at increased risk of infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), transmitting the infection to vulnerable patients if they are not timeously isolated.

AIM: This study aimed to determine the point prevalence of SARS-CoV-2 infection in a cohort of HCWs providing oncology services.

METHODS AND RESULTS: HCWs in a large referral cancer hospital in Egypt were tested using real-time reverse transcription-polymerase chain reaction (RT-PCR) on nasopharyngeal swabs, and immunochromatography-based rapid serological test (RST). Clinical and epidemiological data were collected. In 2020, 999 HCWs were screened, of whom 86 tested positive for SARS-CoV-2 by RT-PCR (8.6%) and 127 subjects were seropositive for antibodies against SARS-CoV-2 by RST (12.8%). Immunoglobulin M seroprevalence demonstrated considerable concordance with RT-PCR positivity (sensitivity 82.14% and specificity 96.71%). Most HCWs (>95%) reported adherence to personal protective equipment. Patient transporters/cleaner were the group with the highest frequency of positive RT-PCR (19%) whereas laboratory and radiology technicians displayed the lowest frequency. Fever, dry cough, rhinorrhea, shortness of breath, fatigue and diarrhea were significantly associated with RT-PCR positivity, with increased likelihood of being positive with the presence of five or six simultaneous symptoms.

CONCLUSIONS: The point prevalence of SARS-CoV-2 infection in screened HCWs is 8.6% by RT-PCR and seroprevalence is 12.8% by RST. Strict measures should be implemented to minimize transmission within healthcare settings and to the community. Our data support the importance of HCWs screening for SARS-CoV-2, taking in account the significant proportion of asymptomatic carriers.
Arrhythmia-induced Cardiomyopathy: An Article Review
Authors: Purwowiyoto Sidhi Laksono , Kusharsamita Hillary
Published: March 2022

Arrhythmia is one of the significant reversible causes in patients with heart disease and left ventricular dysfunction. Tachycardia, atrial fibrillation, and premature ventricular contractions have indeed been related to arrhythmia-induced cardiomyopathy (CM), a reversible dilated CM. Effective arrhythmia suppression will entirely or partially recover ventricular function, lowering morbidity and mortality. However, the importance of arrhythmia-induced CM (ARiCM) is often underestimated in clinical practice because arrhythmia is often seen as a result rather than a cause of CM, leading in treatment delays and failure to increase the quality of life and better clinical outcomes. This article review aims to summarize the pathomechanisms, and a general approach to the management of ARiCM and its long-term outcomes. ARiCM can cause a variety of clinical signs, ranging from asymptomatic to severe heart failure symptoms. Electrocardiogram, 24 h Holter monitoring, echocardiography, and cardiac magnetic resonance are all recommended for diagnosis. More research is required to better understand the pathogenesis of ARiCM and to differentiate treatment alternatives to choose the ideal ARiCM management approach.
Formulation of Orally Disintegrating Tablets of Captopril as Superdisintegrant using Corncob (Zea mays L.)
Authors: Dalimunthe Gabena Indrayani , Samran Samran , Susanto Najarul , Ridwanto Ridwanto , Gurning Kasta
Published: March 2022

AIM: This study aimed to make corncobs the basic material for the manufacture of microcrystalline cellulose.
METHODS: Manufacture of corncob cellulose microcrystals (CCMs) by isolating alpha-cellulose from corncobs, then hydrolyzed with HCl 2.5 N. The yield of CCMs of 14.51% can be used as orally disintegrating tablet (ODT) and has similarities with Avicel as standard comparison.
RESULTS: Both organoleptic results were pH 5.6 and 6.54; drying shrinkage 3.33% and 4.39%; total ash content 0.17% and 0.02%; and water solubility 0.9% and 0.12%. Furthermore, the real specific gravity is 0.317 and 0.306 g/cm3, incompressible density is 0.379 and 0.375 g/cm3, the true density is 1.291 and 1.206 g/cm3, Hausner index is 1.195 and 1.225, compressibility index is 19.55 and 22.55%, and porosity is 75.5 and 74.6%.
CONCLUSION: Captopril ODT tablet preparations with CCM as filler have almost the exact tablet evaluation results compared to Avicel and to meet the requirements.
A Review on Phytochemicals and Pharmacological Activities as Ethnomedicinal Uses of Duku (Lansium domesticum Corr.)
Authors: Lubis Muhammad Fauzan , Hasibuan Poppy Anjelisa , Syahputra Hafid , Astyka Ririn
Published: March 2022

BACKGROUND: Lansium domesticum Corr. is a plant that is easily found in Indonesia. People use the fruit to be sold because it has a good taste. Some people use other parts of the plant as medicine. This plant has great potential to be developed as a standardized traditional medicine.

AIM: This article review aims to collect information on secondary metabolite compounds from L. domesticum Corr. and its pharmacological activities as antioxidants, antibacterials, and cytotoxics.

METHODS: Data on L. domesticum Corr. or duku were sought and collected for this miniature estimate and perspective. We use the major search engines with specific keywords such as L. domesticum Corr.; duku; morphology; pharmacological effects; secondary metabolites; in vitro; and in vivo.

RESULTS: This review shows that L. domesticum Corr. have antioxidant, antibacterial, and cytotoxic activity of various compounds based on the test method used.

CONCLUSIONS: Some parts of L. domesticum Corr. such as leaves, fruit, fruit skins, and seeds contain secondary metabolite compounds. The most common type of active compound is the steroid/terpenoid group. These compounds are responsible for their pharmacological activities such as antioxidants, antibacterials, and cytotoxics.
Case of Insulinoma in a 2-Months-Old Infant
Authors: Pangestika Niluh Putu Wida , Arimbawa I Made , Yuda I Made Darma , Suparyatha Ida Bagus Gede , Wati Dyah Kanya , Hartawan I Nyoman Budi , Ariyanta Kadek Deddy , Darmajaya I Made , Kurniyanta I Putu , Maker Luh Putu Iin Indrayani , Anandasari Pande Putu Yuli , Wande I Nyoman
Published: March 2022

INTRODUCTION: Insulinoma is congenital hyperinsulinism of infancy (CHI). It is a type of functional neuroendocrine tumor (NET) in the pancreas that manifests with persistent hypoglycemia caused by inappropriately high secretion of insulin (hyperinsulinemia). Comprehensive and multidisciplinary management is required for a better outcome.

CASE PRESENTATION: A 2-months-old girl came to the Emergency unit Sanglah Hospital, with a chief complaint of seizure. The patient had a low blood glucose level, high fasting insulin, high LDH, computed tomography of the abdomen result showed isodense heterogeneous lesions border in the cauda pancreas with size 1.32 × 1.24 × 1.35 cm. The anatomy-pathological result showed pancreatic neuroendocrine tumor WHO Grade II, functional, consistent, and clinically to insulinoma on the tail of the pancreas. The patient was treated with hydrocortisone, nifedipine, and octreotide. The patient underwent laparotomy partial pancreatectomy. In post-surgery condition, she had good drink tolerance, no episode of recurrent seizure, and blood glucose was controlled.

CONCLUSION: Insulinoma is a rare disease. The diagnosis was challenging. This case report presents the diagnostic work-up and management of a patient with a persistent hypoglycemia condition that was diagnosed as insulinoma.
Molecular screening for fragile X syndrome in children with unexplained intellectual disability and/or autistic behaviour
Authors: Stoyanova Milena , Hachmeriyan Mari , Levkova Mariya , Bichev Stoyan , Georgieva Miglena , Mladenov Vilhelm , Angelova Lyudmila
Published: March 2022

Introduction: Fragile X syndrome (FXS, OMIM #300624) is the most common inherited form of intellectual disability and the leading monogenic cause of autism. 

Aim: To present our experience with selective screening for FXS among high-risk children with intellectual disability/developmental delay/autistic behaviour and to further prove the importance of performing selective screening in a high-risk population.

Materials and methods: Fifty-two children (45 boys and 7 girls) hospitalized in pediatric clinics or referred to genetic counseling services were tested with triplet repeat primed PCR based commercial kit. The mean age of participants was 6 years (the youngest was 2 years old, the oldest - 15 years old). These patients were selected based on the presence of at least one of the following clinical features: developmental delay, intellectual disability, and autistic-like behaviour.

Results: All patients presented with developmental delay, including language delay. Intellectual disability and autistic-like behaviour were the most consistent features. Thirty-three children (63.4%) were with intellectual disability. Autism and autistic-like behaviour were observed in 22 patients (42.3%). Only 9 male patients (17.3%) presented with dysmorphic features typical for FXS. Three boys (5.7%) were found to be affected and two of their mothers - premutation carriers. 

Conclusions: The present study is the first attempt for molecular genetic selective screening for FXS among high-risk groups in north-eastern Bulgaria. Screening for FXS helps in making a definitive diagnosis along with providing genetic counseling to the family which includes reproductive planning and risk assessment.
Immunological response to nonresorbable barrier membranes used for guided bone regeneration and formation of pseudo periosteum: a narrative review
Authors: Giragosyan Krikor , Chenchev Ivan , Ivanova Vasilena , Zlatev Stefan
Published: March 2022

Here we review the knowledge on the local biological immunological response (formation of “pseudo periosteum” of the host) to two types of nonresorbable membranes used in the horizontal and vertical alveolar ridge augmentation: the titanium-reinforced polytetrafluoroethylene membrane and the titanium mesh membrane. A literature search was conducted including available in vitro, in vivo, and clinical studies on cellular and molecular immunological response to these two types of nonresorbable membranes, in particular the formation of “pseudo periosteum”.

Emerging data demonstrates that despite barrier membranes being considered as bioinert, they still elicit an immunological response from the body. The outcome of this reaction is the formation of a thin fibrous capsule referred to as “pseudo periosteum”.

There are almost no biomaterials that are truly bioinert and this makes no exception for the nonresorbable membranes used in the guided bone regeneration. This iatrogenically made tissue is hypothesized to have a number of advantages and drawbacks. However, more research is needed in that area to truly understand its nature and importance to the guided bone regeneration process.
Quality of life of patients with cardiac pacemaker: levels, associated characteristics, and the impact of anxiety and depression
Authors: Polikandrioti Maria
Published: March 2022

Introduction: Implantation of a permanent cardiac pacemaker (PPM) improves recipients’ quality of life (QoL). However, psychiatric disturbance may adversely affect QoL and undermine clinical outcomes. 

Aim: To explore impact of anxiety and depression on QoL of PPM recipients. 

Materials and methods: A hundred and fifty PPM recipients were enrolled. Data collection was performed by completing the Hospital Anxiety and Depression Scale (HADS) and the SF-36 Health Survey (SF-36). Demographic characteristics were also included. The statistical significance level was p<0.05.

Results: Almost a quarter of the patients experienced anxiety (25.3%) and depression (26.0%). In terms of QoL, patients showed moderate to high levels in social functionality, energy/fatigue, emotional well-being and pain (median: 50, 60, 72, and 67.5, respectively) and poor levels in physical functioning, physical role and emotional role (medians: 22, 0, and 0 respectively). In addition, patients had moderate levels of general health (median 48.5). All QoL subscales were negatively associated with anxiety and depression of patients on a univariate level (p<0.05). Regarding demographic variables affecting QoL, age was statistically significantly associated with physical role (p=0.025), emotional role (p=0.005), social functioning (p=0.033), and pain (p=0.018). Furthermore, physical role was statistically significantly associated with number of children (p=0.024), emotional role with education level (p=0.011), social functioning with family status (p=0.018), and general health with residency (p=0.006). 

Conclusions: Demographic characteristics and anxiety/depression are related with QoL. A better understanding of these associations may help clinicians in planning rational and cost-effective interventions.
RP-HPLC method development and validation for simultaneous estimation of telmisartan, rosuvastatin calcium, and amlodipine besylate in combination
Authors: Mistry Rujuta P. , Shah Chainesh , Jat Rakesh
Published: March 2022

Introduction: Dyslipidemia-hypertension proves to be a major risk factor for cardiovascular diseases. In order to achieve better adherence and cost-effectiveness than free equivalent combination therapies, a fixed-dose combination therapy with telmisartan (TEL), rosuvastatin calcium (ROS) and amlodipine besylate (AML) is required in this type of patients. 

Aim: A simple, selective and reproducible reverse phase high performance liquid chromatography (RP-HPLC) method has been developed and validated for estimation of telmisartan, rosuvastatin calcium, and amlodipine besylate in synthetic mixture. 

Materials and methods: Chromatographic separation was performed on a reversed-phase Luna C18 100Å column (250 mm × 4.6 mm i.d., particle size 5 μ) using an isocratic elution of mobile phase consisting of methanol and acetonitrile (pH 3.5 adjusted by ortho-phosphoric acid) (60:40 v/v) at a flow rate of 1.0 ml/min. 

Results: Ultraviolet (UV) detection was performed at 242 nm and retention time of telmisartan, rosuvastatin calcium and amlodipine besylate was found to be 2.67, 4.70, and 7.44 min, respectively. The calibration curve was linear (correlation coefficient >0.999) in the selected range of analyte. 

Conclusions: The method was validated for accuracy, precision, linearity, limit of detection, limit of quantitation and ruggedness. The system suitability parameter, such as theoretical plate, asymmetry, and resolution between standard five replicate were well within the limits.  
Time Since Rituximab Treatment Is Essential for Developing a Humoral Response to COVID-19 mRNA Vaccines in Patients With Rheumatic Diseases
Authors: Troldborg Anne , Thomsen Marianne Kragh , Bartels Lars Erik , Andersen Jakob Bøgh , Vils Signe Risbøl , Mistegaard Clara Elbæk , Johannsen Anders Dahl , Hermansen Marie-Louise From , Mikkelsen Susan , Erikstrup Christian , Hauge Ellen-Margrethe , Ammitzbøll Christian
Published: March 2022

Objective.

We aimed to investigate (1) whether patients with rheumatic disease (RD) treated with rituximab (RTX) raise a serological response toward the coronavirus disease 2019 (COVID-19) mRNA vaccines, and (2) to elucidate the influence of time since the last RTX dose before vaccination on this response.

Methods.

We identified and included 201 patients with RDs followed at the outpatient clinic at the Department of Rheumatology, Aarhus University Hospital, who had been treated with RTX in the period 2017–2021 and who had completed their 2-dose vaccination series with a COVID-19 mRNA vaccine. Total antibodies against the SARS-CoV-2 spike protein were measured on all patients and 44 blood donors as reference.

Results.

We observed a time-dependent increase in antibody response as the interval from the last RTX treatment to vaccination increased. Only 17.3% of patients developed a detectable antibody response after receiving their vaccination ≤ 6 months after their previous RTX treatment. Positive antibody response increased to 66.7% in patients who had RTX 9–12 months before vaccination. All blood donors (100%) had detectable antibodies after vaccination.

Conclusion.

Patients with RDs treated with RTX have a severely impaired serological response toward COVID-19 mRNA vaccines. Our data suggest that the current recommendations of a 6-month interval between RTX treatment and vaccination should be reevaluated.
Young-GRAPPA at the Annual GRAPPA Meeting: Presentation of a New Group Within GRAPPA and Its Vision
Authors: van Mens Leonieke , Ayan Gizem , Coates Laura C. , Coras Roxana , Silva Dimitri L.F. , Herrera Sebastián , Ishchenko Alla , Jethwa Hannah , Johnsson Hanna , Simon David , Vivekanantham Arani , Proft Fabian
Published: March 2022

At the 2021 Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) annual meeting, a separate group was created (Young-GRAPPA) to address the challenges of young researchers and physicians beginning their careers. This paper presents the initial organizational framework and different components and aims of this group. We were able to enroll over 50 young researchers as a result of this meeting.
Geometry of the line space associated to a given dual ruled surface
Authors: Hussein Rawya A. ,   Mathematics Department, Faculty of Science, Assiut University, Assiut, Egypt, Ali Ali A. ,   Department of Mathematics, College of Science and Arts, AlMithnab, Qassim University, Buridah 51931, Saudi Arabia
Published: March 2022

As a continuation to our results in [1], we study the dual ruled surface defined on the set of dual numbers. The idea of the dual part are defined similar to quaternion space. The dual part of this represents a ruled dual submanifold. The geometric properties of their dual parts are investigated. Some examples are given and plotted.