Future Online Radiology Education: The Importance of Curriculum

Mohamed Shah Mohammad Taufik Bin,Yeong Lim Chee,Cheng Lionel Tim-Ee,Ang Jessica,Lishan Yang,Tan Kevin,Lim Choie Cheio Tchoyoson 대한영상의학회 2023 Korean Journal of Radiology Vol.24 No.3

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The effect of thermocycling on the bonding of different restorative materials to access opening through porcelain fused to metal restorations

Mohammed M. AL-Moaleem,Farhan Khalid Shah,Nausheen Saied Khan,Amit Porwal 대한치과보철학회 2011 The Journal of Advanced Prosthodontics Vol.3 No.4

PURPOSE Porcelain fused to metal (PFM) crowns provide the best treatment option for teeth that have a large or defective restoration. More than 20% of teeth with PFM crowns or bridges require non-surgical root canal treatment (NSRCT). This may be due to the effect of restorative procedures and the possible leakage of bacteria and or their by-products, which leads to the demise of the tooth pulp. Thus, this study was planned to compare the ability of the restorative materials to seal perforated PFM specimens. MATERIALS AND METHODS The study evaluates the ability of amalgam, composite or compomer restorative materials to close perforated PFM specimen's in-vitro. Ninety PFM specimens were constructed using Ni-Cr alloys and feldspathic porcelain, and then they were divided into 3 groups: amalgam (A), composite + Exite adhesive bond (B) and compomer + Syntac adhesive bond (C). All the PFM samples were embedded in an acrylic block to provide complete sealing of the hole from the bottom side. After the aging period, each group was further divided into 3 equal subgroups according to the thermocycling period (one week for 70 cycles, one month for 300 cycles and three months for 900 cycles). Each subgroup was put into containers containing dye (Pelikan INK), one maintained at 5℃ and the other at 55℃, each cycle for 30 sec time. The data obtained was analyzed by SPSS, 2006 using one way ANOVA test and student t-test and significant difference level at (P<.01). RESULTS The depth of dye penetration was measured at the interfaces of PFM and filling materials using Co-ordinate Vernier Microscope. The lowest levels of the dye penetration for the three groups, as well as subgroups were during the first week. The values of dye leakage had significantly increased by time intervals in subgroups A and C. CONCLUSION It was seen that amalgam showed higher leakage than composite while compomer showed the lowest level of leakage.

Early wake-up decision algorithm for ONUs in TDM-PONs with sleep mode

Mohammed, Alaelddin Fuad Yousif,Newaz, S. H. Shah,Uddin, Mohammad Rakib,Lee, Gyu Myoung,Choi, Jun Kyun IEEE 2016 Journal of optical communications and networking Vol.8 No.5

<P>Recent IEEE and ITU-T standards for time division multiplexing-passive optical networks (TDM-PONs) with sleep mode recommend that the optical line terminal (OLT) in a TDM-PON should be in charge of invoking the optical network units (ONUs) to move into the sleep state in the absence of frames. It is considered that, upon upstream frame arrival, a sleeping ONU can leave the sleep state, in which an ONU turns off its transmitter or both its transmitter and receiver, immediately, prior to its assigned sleep interval length. In this paper, we refer to this approach as immediate early wake-up (IMEW). According to the standards, the OLT may or may not allow an ONU to trigger an early wake-up function (EWF) upon the upstream frames' arrival. If the OLT does not allow the EWF [we refer to this as not support early wake-up (NSEW)], an ONU should stay in the sleep state during its assigned sleep duration and buffer all the upstream frames while it is in this state. In IMEW, the upstream frames experience a small delay, but the ONU's energy consumption increases remarkably. Conversely, in NSEW, an ONU consumes less energy compared to IMEW at the price of increasing the upstream frame delay and the possibility of having its buffer overflow. In this paper, the limitations of IMEW and NSEW have motivated us to propose a novel early wake-up decision (EWuD) algorithm that aims at meeting the upstream frame delay requirement while reducing the ONUs' energy consumption as much as possible. The role of the EWuD algorithm is to select an appropriate time for triggering EWF, taking into consideration two factors: 1) buffer overflow probability and 2) delay requirement violation of upstream frames. We evaluate EWuD performances using our TDM-PON OPNET modular-based simulation model under a wide range of scenarios. The findings demonstrate that our proposed EWuD can successfully meet the delay requirements of all upstream frames while reducing the ONUs' energy consumption significantly.</P>

Coronavirus Disease 2019 Transmission: Blood Viremia and Aerosol Generation from Spinal Surgery. Is There an Increased Risk to the Surgical Team?

Shah Siddharth,Gadiya Akshay,Patel Mohammed Shakil,Shafafy Masood 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.5

As a respiratory pathogen, the novel coronavirus is commonly associated with aerosol-generating procedures. However, it is currently unclear whether spinal surgical procedures pose an additional risk of viral transmission to the surgical team. We reviewed the available evidence to ascertain the presence of coronavirus disease 2019 (COVID-19) blood viremia and the virus’ blood transmissibility, as well as evidence of blood-aerosol generation and operating room contamination from spinal surgical procedures. There is established evidence of COVID-19 blood viremia, a viral pathogenic cycle via angiotensin-converting enzyme 2 (ACE-2) receptors and similar blood transmission risk data from the SARS (severe acute respiratory syndrome)/MERS (Middle East respiratory syndrome) era. Spinal surgical practices demonstrate significant blood-aerosol generation from the operative wound due to the use of common surgical instruments, such as electrocautery, as well as high-speed and high-impact devices. Based on the evidence, there is an established additional risk of viral transmission faced by surgical teams from blood-aerosols generated from the operative wound of COVID-19- infected patients via the inhalation of virus-laden aerosols and the subsequent initiation of the viral pathogenic cycle through binding with pulmonary ACE-2 receptors. Recognizing this additional risk amidst the ongoing pandemic serves as a caution to front-line surgical personnel to strictly adhere to personal protective equipment usage in operating rooms, to modify surgical techniques to reduce the hazard of surgical aerosol generation and COVID-19 viral exposure, and to consider it as an integral aspect of planning and adapting to the “new normal” operating practices.

Insecticide resistance monitoring in whitefly (Bemisia tabaci) (Hemiptera: Aleyrodidae) in Oman

Shah Riaz,Al-Sadi Abdullah Mohammed,Scott Ian M.,AlRaeesi Ali,AlJahdhami Ali Abdullah 한국응용곤충학회 2020 Journal of Asia-Pacific Entomology Vol.23 No.4

The sweet potato whitefly, Bemisia tabaci Gennadius, is an important insect pest of many crops including vegetables through direct feeding damage and as a vector of several plant viruses. Intensive use of insecticides has led to the development of insecticide resistance in global B. tabaci populations. This study was conducted to establish susceptibility levels to deltamethrin, thiamethoxam and pyriproxyfen in seven geographically different populations of B. tabaci MEAM1 adults in Oman. All B. tabaci populations showed very low to low level of resistance (2.1–12.3 fold) to deltamethrin. All B. tabaci populations showed no resistance to very low level of resistance to thiamethoxam (2.2–6.2 fold) and pyriproxyfen (2.4–3.5 fold). A likelihood analysis showed the possibility for control failure in two populations (Barka and Salalah) to deltamethrin, however, no possible failure was detected in all populations for thiamethoxam and pyriproxyfen. An insecticide resistance dynamics study in one population (SQU-1) showed a loss in susceptibility to deltamethrin with increase in the LC 50 value from 25.1 mg L −1 to 84.5 mg L −1 between 2017 and 2019 resulting in 5.3 fold increase in RF. The study results determined that several B. tabaci populations are at the initial stages of resistance development to deltamethrin and cross-resistance with thiamethoxam and pyriproxyfen. Vegetable farmers in Oman, the Barka and Salalah regions in particular, should be cautious in the repeated use of one class of insecticide alone.

Composition and diversity of plants in Sibuti mangrove forest, Sarawak, Malaysia

Kaleem Shah,Abu Hena Mustafa Kamal,Zamri Rosli,Khalid Rehman Hakeem,Mohammed Muzammel Hoque 한국산림과학회 2016 Forest Science And Technology Vol.12 No.2

Sarawak is endowed with numerous pristine and estuarine mangroves. However, information pertaining to the species composition and diversity of pristine mangroves of Sarawak is scanty. Hence, this study was carried out to assess the plant composition and diversity of Sibuti mangrove forest, Miri, Sarawak to investigate the current status and diversity of vegetation. Nine mangrove plant species were recorded employing the line transect (100240 m) survey method. Major mangrove species were Rhizophora apiculata, Xylocarpus granatum, and Nypa fruticans. The stand density was recorded as 1938.46 § 482.24 trees ha ¡1, 1722.22 § 254.58 saplings ha ¡1, and 6222.22 § 384.90 seedlings ha ¡1. The mean diameter, height, and basal area for the whole forest stand were 20.83 § 13.79 cm, 13.53 § 5.55 m, and 201.83 § 12.68 m2 ha ¡1, respectively. The mean diameter of the dominant species R. apiculata was 24.10 § 13.90 cm, height 15.18 § 5.09 m, and basal area 176.13 § 12.73 m2 ha ¡1. The importance value index (IVI) of R. apiculata was 202.24 followed by 63.85 for X. granatum. Shannon diversity indices (H0), Margalef richness (D), and Peilou evenness (J0) of the forest stand were 1.18, 1.41, and 0.54, respectively. Similarity of species composition showed two major clusters for the whole forest stand. The findings of this study suggest that Sibuti mangrove forest stand is undisturbed and healthy. This forest could be managed and conserved for multi-sectoral uses such as ecotourism, biodiversity, research, and education rather than solely as a wildlife sanctuary.

Influences of Microbial Ferment on in vitro Seed Germination and Seedling Growth of Four Forest Tree Species

Shailendra Kumar. Shah,Hui-lian Xu,Mohammed Kamal. Hossain 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

Development of Pozzolanic material from clay

Alaskar, Abdulaziz,Shah, S.N.R.,Keerio, Manthar Ali,Phulpoto, Javed Ali,Baharom, Shahrizan,Assilzadeh, Hamid,Alyousef, Rayed,Alabduljabbar, Hisham,Mohamed, Abdeliazim Mustafa Techno-Press 2020 Advances in concrete construction Vol.10 No.4

The following paper concentrates on the objective of studying the influences of extent of duration and temperature on the Pozzolanic properties as well as reactivity of locally existing natural clay of Nai Gaj, district Dadu, Sindh Pakistan. The activation of the clay only occurs through heating when temperature in a furnace chamber reaches 600, 700 and 800oC for 1, 2 and 3 hours and at 900 and 1000℃ for 1 and 2 hours. Furthermore, the strength activity index (SAI) of advanced pozzolanic material happens to be identified through 20% cement replacement for different samples of calcined clay as per ASTM C-618. The compressive strength test of samples had been operated for 7 and 28-days curing afterwards. The maximum compressive strength had been seen in mix E in which cement was replaced with clay calcined at 700℃ for 1 hour that is 27.05 MPa that is 24.31% more than that of control mix. The results gathered from the SAI verdicts the optimal activation temperature is 700℃ within a one-hour time period. The SAI at a temperature of 700℃ with a one-hour duration at 28 days is 124.31% which happens to satisfy the requirements of the new Pozzolanic material, in order to be applied in mortar/concrete (i.e., 75%). The Energy- dispersive spectrometry (EDS) along with the X-ray diffraction (XRD) have been carried out in means of verifying whether there is silica content or amorphous silica present in metakaolin that has been developed. The findings gathered from the SAI were validated, as the analysis of XRD verified that there is in fact Pozzolanic activity of developed metakaolin. Additionally, based on observation, the activated metakaolin holds a significant influence on the increase in mortar's compressive strength.

A new phantom to evaluate the tissue dissolution ability of endodontic irrigants and activating devices

Khoshroo Kimia,Shah Brinda,Johnson Alexander,Baeten John,Barry Katherine,Tahriri Mohammadreza,Ibrahim Mohamed S.,Tayebi Lobat 대한치과보존학회 2020 Restorative Dentistry & Endodontics Vol.45 No.4

Objective: The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. Materials: and Methods Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. Results: The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. Conclusions: Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.

Pattern of Lymph Node Pathology in Western Saudi Arabia

Albasri, Abdulkader Mohammed,El-Siddig, Abeer Abdalla,Hussainy, Akbar Shah,Alhujaily, Ahmed Safar Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

Background: This study aimed to characterize the histopathological pattern of lymph node pathology among Saudi patients and to highlight the age and gender variations of these lesions as base line data. Materials and Methods: We retrospectively analyzed the data from lymph node biopsy specimens received at the Department of Pathology, King Fahad Hospital, Madinah, Saudi Arabia from January 2006 to December 2013. Results: Of the 289 lymph node biopsy specimens received, 154 (53.3%) were from males and 135 (46.7%) from females giving a male: female ratio of 1.14:1. Age of the patients ranged from 2.5 to 96 years with a mean age 33.9 years. The commonest lymph node group affected was the cervical (30.4%) followed by axillary (9.7%) and inguinal (8.7%). Malignant lymphoma [71 Hodgkin's disease (HD), 57 non Hodgkin's lymphoma (NHL)] 128 (44.3%), reactive hyperplasia 68 (23.5%), and tuberculosis 41 (14.2%) were the common causes of lymph node enlargement. While HD, reactive hyperplasia and tuberculosis were commonest in young adult patients (10-29 years old) and rare above the age of 50 years; NHL was the predominant cause of lymph node enlargement above 50 years. Conclusions: Lymph node biopsy plays an important role in establishing the cause of lymphadenopathy. Among the biopsied nodes, lymphomas were the most common (44.3%) followed by non-specific reactive hyperplasia (23.5%) and tuberculous lymphadenitis (14.2%).