10 research outputs found
Development of expert project management system (EPMS) in Android / Che Mohamad Anis Che Mat
No full textExpert Project Management System or EPMS developed to apply the latest technology of android into the project management system. In the previous system that has been developed, it is became a problem as it is developed under windows system or a web-based system that running on a laptop or pc. The size of the device itself has making a burden for them to carry a laptop to any project site to ensure they can check project progress. Another problem that been face by user is the difficulties to track down each cost that has been used for the project. By having Expert Project Management System, project manager can use the software using their android mobile device. This way project manager can bring the software and use anywhere without any difficulties as it is in a size that is small enough for them to use. By having Expert Project Management System also, project manager can track the budget that has been use for the project easily and can save them from excessing the budget. There are three objective that must be achieved in the project. The first objective is to develop android based application on the project management system. The second objective is to develop function to keep track of the progress and cost and the third objective is to create final assessment on the project based on the project progress. The development of Expert Project Management System is based on Rapid Application Development as it allow fast implementation of the system in real environment. The development start with Analysis and quick design and move on to prototype circles where develop, demonstrate and refine happen. It then procedd to testing and deployment
Publication productivity of Malaysian researchers in the field of Computer Science and Information Technology
No full textSearches made in the CD-ROM databases, COMPENDEX (1987-1999), IEL (IEE/IEEE Electronic Library) (1988-1999) and INSPEC (1990-1998) revealed a total of 389 publications contributed by Malaysian researchers in the field of computer science and information technology. The trend in output indicates rapid growth that is expected to continue in future. A total of 458 unique Malaysian authors contributed to the 389 publications. Collaboration between two authors was the dominant authorship pattern. Single-authored or more than 3-authored works were rare. The active authors were affiliated to a few institutions, with the Universiti Teknologi Malaysia, Universiti Sains Malaysia and Universiti Malaya accounting for the highest number of publications, either in the form of journalarticles or papers in conference proceedings. The most active research areas include simulation system, control engineering, computer-assisted instruction, programming techniques, expert systems, asynchronous transfer mode, image processing, software engineering and digital signal processing and applications
Olive oil by-products in aquafeeds: opportunities and challenges
No full textThe increment in world population has led to the increasing demands for fish supply as principal source of animal protein that represents about 17% of animal protein consumption globally. The world aquaculture industry has expanding remarkably but limited source of fishmeal and fish oil which known as important ingredients in fish feed has led to seeking of alternative sources for their replacement in aquafeed formulation. Many potential and cheaper ingredients derived from vegetable oils or agricultural by-products have been investigated to replace fish meal and fish oil which shown promising results in fish productivity and fish health status including olive oil by- products. Varies depending on its type, olive oil composes of antioxidants, healthy type of fats such as MUFA and PUFA, and high in vitamins that provide human health benefits for heart and liver, help in many diseases and reducing the risk of cancer. In agriculture industry, olive and olive oil production processes have resulted to by- products such as olive mill wastewater (OMW), olive leaf and olive pomace. The inclusion of these by-products in animal feeds is the solution for agricultural waste management. The first report of utilization of olive oil by- products in fish feed was documented in 2004 and since then, many researches has been conducted to investigate fish health benefits that showed improvement in fish carcass composition and fish immunity depending on type of by-products used and fish species. Additionally, antioxidant contents in olive oil extract were reported could provide antimicrobial, antifungal and antioxygenic characteristics which potentially improve the fish health. This review discussed the opportunities and challenges in application of olive oil by-products in aquafeed which provides significant prospects in fish growth performance that could boost aquaculture industry development
Palm date meal as a non-traditional ingredient for feeding aquatic animals: A review
No full textProtein ingredients in aquafeed are one of the most important factors responsible for the development and sustainability of aquaculture. Currently, because of high costs and fluctuating production, some animal and plant protein sources are unable to satiate the increasing demand from the fish feed manufacturers. Aquatic animals’ nutritional requirements have been accorded particular focus with less costly feedstuff in aqua feed given extra weightage. There has been increasing attention in recent years on finding methods to recycle the animal and plant by-products for feed preparation. Due to its vital amino acid content as well as high protein composition, palm date meal (PDM) which is a renewable and sustainable resource is expected to be a viable raw material option for replacing protein ingredients (e.g., fish meal and soybean meal) or as a supplement in fish feed. PDM is an agro-industry by-product which left from dates as waste in several countries. This article reviewed the current research including the source, derivatives, and the potential of PDM as a possible alternative to the conventional plant and animal protein sources. Also, the added value of using PDM waste in aquafeed to reduce the feed cost, enhance this e growth rate of fish, improve the health and well-being of fish, and subsequently sustain the aquaculture industry. Therefore, this review paper will illuminate the possibility of PDM as a promising feed source and also the present knowledge and future perspectives about the application of PDM in aquaculture
Editorial
No full text(IIUMEJ)
IIUM ENGINEERING JOURNAL
ISSN: 1511-788X E-ISSN: 2289-7860
Volume 19, Issue 2, December 2018
https://doi.org/10.31436/iiumej.v19i2
CHIEF EDITOR
Ahmad Faris Ismail, IIUM, Malaysia
TECHNICAL EDITOR
Erry Yulian Triblas Adesta, IIUM, Malaysia
EXECUTIVE EDITOR
AHM Zahirul Alam, IIUM, Malaysia
ASSOCIATE EDITOR
Anis Nurashikin Nordin, IIUM, Malaysia
LANGUAGE EDITOR
Lynn Mason, Malaysia
COPY EDITOR
Hamzah Mohd. Salleh, IIUM, Malaysia
EDITORIAL BOARD MEMBERS
Abdullah Al-Mamun, IIUM, Malaysia
Abdumalik Rakhimov, IIUM, Malaysia
Amir Akramin Shafie, IIUM, Malaysia
Erwin Sulaeman, IIUM, Malaysia
Hanafy Omar, Saudi Arabia
Hazleen Anuar, IIUM, Malaysia
Konstantin Khanin, University of Toronto, Canada
Ma'an Al-Khatib, IIUM, Malaysia
Md Zahangir Alam, IIUM, Malaysia
Meftah Hrairi, IIUM, Malaysia
Mohamed B. Trabia, United States
Mohammad S. Alam, Texas A&M University-Kingsville, United States
Muataz Hazza Faizi Al Hazza, IIUM, Malaysia
Mustafizur Rahman, National University Singapore, Singapore
Nor Farahidah Binti Za'bah, IIUM, Malaysia
Ossama Abdulkhalik, Michigan Technological University, United States
Rosminazuin AB. Rahim, IIUM, Malaysia
Waqar Asrar, IIUM, Malaysia
INTERNATIONAL ADVISORY COMMITTEE
A. Anwar, United States
Abdul Latif Bin Ahmad, Malaysia
Farzad Ismail, USM, Pulau Pinang, Malaysia Hanafy
Omar, Saudi Arabia
Hany Ammar, United States
Idris Mohammed Bugaje, Nigeria
K.B. Ramachandran, India Kunzu Abdella, Canada
Luis Le Moyne, ISAT, University of Burgundy, France
M Mujtaba, United Kingdom
Mohamed AI-Rubei, Ireland Mohamed B Trabia, United States
Mohammad S. Alam, Texas A&M University-Kingsville, United States
Nazmul Karim
Ossama Abdulkhalik, Michigan Technological University, United States
Razi Nalim, IUPUI, Indianapolis, Indiana, United States
Syed Kamrul Islam, United States
Tibor Czigany, Budapest University of Technology and Economics, Hungary
Yiu-Wing Mai, The University of Sydney, Australia.
AIMS & SCOPE OF IIUMENGINEERING JOURNAL
The IIUM Engineering Journal, published biannually, is a carefully refereed international publication of International Islamic University Malaysia (IIUM). Contributions of high technical merit within the span of engineering disciplines; covering the main areas of engineering: Electrical and Computer Engineering; Mechanical and Manufacturing Engineering; Automation and Mechatronics Engineering; Material and Chemical Engineering; Environmental and Civil Engineering; Biotechnology and Bioengineering; Engineering Mathematics and Physics; and Computer Science and Information Technology are considered for publication in this journal. Contributions from other areas of Engineering and Applied Science are also welcomed. The IIUM Engineering Journal publishes contributions under Regular papers, Invited review papers, Short communications, Technical notes, and Letters to the editor (no page charge). Book reviews, reports of and/or call for papers of conferences, symposia and meetings, and advances in research equipment could also be published in IIUM Engineering Journal with minimum charges.
REFEREES’ NETWORK
All papers submitted to IIUM Engineering Journal will be subjected to a rigorous reviewing process through a worldwide network of specialized and competent referees. Each accepted paper should have at least two positive referees’ assessments.
SUBMISSION OF A MANUSCRIPT
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Table of Content
EDITORIAL............................................................................................... i
CHEMICAL AND BIOTECHNOLOGY ENGINEERING
CHLORELLA VULGARIS LOGISTIC GROWTH KINETICS MODEL IN HIGH CONCENTRATIONS OF AQUEOUS AMMONIA................... 1
Azlin Suhaida Azmi, Nurain Atikah Che Aziz, Noor Illi Mohamad Puad, Amanatuzzakiah Abdul Halim, Faridah Yusof, Suzana Yusup
SYNTHETIC ANTIMICROBIAL AGENT AND ANTIMICROBIAL FABRICS: PROGRESS AND CHALLENGES............. 10
Norashikin Binti Mat Zain, John Olabode Akindoyo, Mohammad Dalour Hossen Beg
CIVIL AND ENVIRONMENTAL ENGINEERING
PERFORMANCE OF HIGH STRENGTH LIGHTWEIGHT CONCRETE USING PALM WASTES................................... 30
Md. Nazmul Huda, Mohd Zamin Jumaat, Abul Bashar Mohammad Saiful Islam, Walid Abubaker Al-Kutti
ELECTRICAL, COMPUTER AND COMMUNICATIONS ENGINEERING
WIDE RANGE MODULATION INDEXES FEATURED CARRIER-BASED PWM STEPPED WAVEFORM FOR HALF- BRIDGE MODULAR MULTILEVEL CONVERTERS......................................................................................... 43
Majdee Tohtayong, Sheroz Khan, Mashkuri Yaacob, Siti Hajar Yusoff, Nur Shahida Midi, Musse Muhamud Ahmed
A NOVEL METHOD TO ESTIMATE ECONOMIC REPLACING TIME OF TRANSFORMER USING MONTE CARLO ALGORITHM AND ANN............................................................................................... 54
Mehdi Zareian Jahromi, M. Hossein Mehrabanjahromi, Mohsen Tajdinian, Mehdi Allahbakhshi
ADAPTIVE TRIMMED MEAN AUTOREGRESSIVE MODEL FOR REDUCTION OF POISSON NOISE IN SCINTIGRAPHIC IMAGES.......... 68
Khan Bahadar Khan, Muhammad Shahid, Hayat Ullah, Eid Rehman, Muhammad Mohsin Khan
EVALUATION OF THE W-METRIC ROUTING USING RPL PROTOCOL IN LLNS........................................................................ 80
Rosminazuin Ab Rahim, Abdallah M. Awwad, Aisha Hasan Abdalla, Aliza Aini Md Ralib INVESTIGATION ON NEED FOR SPECIFIC PROPAGATION MODEL FOR SPECIFIC ENVIRONMENT BASED ON DIFFERENT TERRAIN CHARACTERISTICS...................90
Jide Julius Popoola, Akinlolu Adediran Ponnle, Yekeen Olajide Olasoji, Samson Adenle Oyetunji
A STUDY ON LOW-COMPLEXITY TRANSMIT ANTENNA SELECTION FOR GENERALIZED SPATIAL
MODULATION.................................................................................. 105
Simeon Olumide Ajose, Adewale Akanbi Alafia, Agbotiname Lucky Imoize
A NEW SPECTRUM AND ENERGY AWARE ROUTING PROTOCOL IN COGNITIVE RADIO SENSOR NETWORK.............................. 118
Sara Moshtaghi, Sayyed Majid Mazinani
RECENT TRENDS IN DENGUE DETECTION METHODS USING BIOSENSORS................................................................................ 134
Ahmad Anwar Zainuddin, Anis Nurashikin Nordin, Rosminazuin Ab Rahim
NUMERICAL ANALYSIS OF TUNNEL LED LIGHTING MAINTENANCE FACTOR.......................................................................... 154
Mehmet Sait Cengiz, Çiğdem Cengiz
ENGINEERING MATHEMATICS AND APPLIED SCIENCE
ABOUT THE SILICON SENSITIVITY OF THE DEEP LEVEL WITH ALTERNATING PRESSURE................................... 164
Ikrom Gulamovich Tursunov, Abdurahim Abduraxmonovich Okhunov, Odiljon Oxundadaevich Mamatkarimov
THE HYDRODYNAMIC COEFFICIENTS FOR OSCILLATING 2D RECTANGULAR BOX USING WEAKLY COMPRESSIBLE SMOOTHED PARTICLE HYDRODYNAMICS (WCSPH) METHOD................................................................................. 172
Muhammad zahir ramli
AN ANALYTICAL TECHNIQUE TO OBTAIN HIGHER-ORDER APPROXIMATE PERIODS FOR THE NONLINEAR OSCILLATOR................... 182
Md Sazzad Hossien Chowdhury, Md. Alal Hosen, Mohammad Yeakub Ali, Ahmad Faris Ismail
MATERIALS AND MANUFACTURING ENGINEERING
EFFECT OF POLY (ETHYLENE GLYCOL) ON THE INJECTABILITY, SETTING BEHAVIOR AND MECHANICAL PROPERTIES OF CALCIUM PHOSPHATE BONE CEMENT.........................................................192
Sufiamie Hablee, Iis Sopyan, Maizirwan Mel, Hamzah Mohd. Salleh, Md. Mujibur Rahman
MECHANICAL AND AEROSPACE ENGINEERING
STUDY OF MESH QUALITY IMPROVEMENT FOR CFD ANALYSIS OF AN AIRFOIL................................................ 203
Farah Aqilah, Mazharul Islam, Franjo Juretic, Joel Guerrero, David Wood, Farid Nasir Ani
MECHATRONICS AND AUTOMATION ENGINEERING
COLOR RECOGNITION WEARABLE DEVICE USING MACHINE LEARNING FOR VISUALY IMPAIRED PERSON................................... 213
Tarek Mohamed Bolad , Nik Nur Wahidah Nik Hashim, Noor Hazrin Hany Mohamad Hanif
COMBINATION OF FUSED DEPOSITION MODELLING WITH ABRASIVE MILLING FOR ATTAINING HIGHER DIMENSIONAL ACCURACY AND BETTER SURFACE FINISH ..................................... 221
Abu Naser Mohammad Amanullah Tomal, Tanveer Saleh, Md Raisuddin Khan
Whilst every effort is made by the publisher and editorial board to see that no inaccurate or misleading data, opinion or statement appears in this Journal, they wish to make it clear that the data and opinions appearing in the articles and advertisement herein are the responsibility of the contributor or advertiser concerned. Accordingly, the publisher and the editorial committee accept no liability whatsoever for the consequence of any such inaccurate or misleading data, opinion or statement.
Published by:
IIUM Press,
International Islamic University Malaysia Jalan Gombak, 53100 Kuala Lumpur, Malaysia Phone (+603) 6196-5014, Fax: (+603) 6196-6298
Website: http://www.iium.edu.my/office/iiumpres
Coconut Palm: Food, Feed, and Nutraceutical Properties
No full textSIMPLE SUMMARY: Different components of the coconut are being looked into and used as a potential substitute to create or substitute animal feed components. Different coconut products and by-products—such as coconut water, milk, copra, testa, flour, raw kernels, oil, and desiccated coconut—are used with livestock, especially ruminants and aquaculture industries. However, the use of coconut in animal feed may be limited by several things that make it less nutritious. There is a possibility to research new technologies, such as pre-treating coconut to reduce the effects of anti-nutritional substances before they can be used to feed the animals. This review article describes a few important discoveries, which gives a somewhat hopeful view of the future. Different parts of the coconut can and should be used more in animal feed. Coconut in animal feed makes it much cheaper to feed animals and helps them in the digestion process, growth, and health. However, innovative methods of processing, extracting, and treating coconut need to be encouraged to improve nutritional quality and make coconut products function efficiently in feed. ABSTRACT: The price of traditional sources of nutrients used in animal feed rations is increasing steeply in developed countries due to their scarcity, high demand from humans for the same food items, and expensive costs of raw materials. Thus, one of the alternative sources is coconut parts or coconut as a whole fruit. Coconut is known as the ‘tree of abundance’, ‘tree of heaven’, and ‘tree of life’ owing to its numerous uses, becoming a very important tree in tropical areas for its provision of food, employment, and business opportunities to millions of people. Coconut contains a rich profile of macro and micronutrients that vary depending on the parts and how they are used. It is frequently chosen as an alternative source of protein and fiber. Its uses as an antibacterial agent, immunomodulant, and antioxidant further increase its importance. Using coconut oil in ruminant feed helps to minimize methane gas emissions by 18–30%, and to reduce dry matter intake up to 4.2 kg/d. The aquaculture sectors also use coconut palm as an alternative source because it significantly improves the digestion, growth, lipid metabolism, health, and antioxidative responses. However, coconut is not widely used in poultry diets although it has adequate amount of protein and carbohydrate due to anti-nutritional factors such cellulose (13%), galactomannan (61%), and mannan (26%). This review considered the importance and potential of coconut usage as an alternative ingredient in feed and supplements in various livestock sectors as it has plentiful nutrients and functional qualities, simultaneously leading to reduced feed cost and enhanced production
Effect of Fish Meal Substitution with Black Soldier Fly (Hermetia illucens) on Growth Performance, Feed Stability, Blood Biochemistry, and Liver and Gut Morphology of Siamese Fighting Fish (Betta splendens)
No full textInsects such as black soldier fly larvae (BSFL) are gaining interest among researchers and the aquafeed industry due to the fluctuating price and supply of fish meal (FM). This study evaluated the growth performance, feed stability, blood biochemistry, and liver and gut morphology of Betta splendens using BSFL as an alternative to FM. Five formulated diets were prepared: 0% BSFL, 6.5% BSFL, 13% BSFL, 19.5% BSFL, and 24.5% BSFL. The expansion rate, pellet durability index, floatability, bulk density, and water stability of the prepared feed have been assessed. Except for the diameter of the feed, all the parameters studied differed significantly (p<0.05) across the experimental diets. After 60 days, the fish fed with 13% BSFL had the highest final length, final weight, net weight gain, specific growth rate, weight gain, and gastrointestinal weight, with mean and standard deviation values of 3.97±0.43 cm, 3.95±0.1 g, 2.78±0.1 g, 4.63±0.17, 4.65±0.13, 237.26±7.9%, and 0.04±0.01 mg, respectively. Similar blood haematology and biochemical properties, including corpuscular volume, lymphocytes, white blood cells, red blood cells, haematocrit, albumin, and alkaline phosphatase, were the highest (p<0.05) in the 13% BSFL diet group compared to the other treatment groups. In addition, BSFL had a significant impact (p<0.05) on villus length, width, and crypt depth for the anterior and posterior guts of B. splendens. The 13% BSFL diet group had an intact epithelial barrier in the goblet cell arrangement and a well-organized villus structure and tunica muscularis, compared to the other treatment groups. Furthermore, the liver cell was altered with different BSFL inclusions; the 13% FM group demonstrated better nuclei and cytoplasm structure than the other treatment groups. In conclusion, replacing 13% FM with BSFL could improve the growth performance, blood parameters, and liver and intestine morphology of B. splendens, thus providing a promising alternative diet for ornamental freshwater fish
Effect of Fish Meal Substitution with Black Soldier Fly (Hermetia illucens) on Growth Performance, Feed Stability, Blood Biochemistry, and Liver and Gut Morphology of Siamese Fighting Fish (Betta splendens)
No full textInsects such as black soldier fly larvae (BSFL) are gaining interest among researchers and the aquafeed industry due to the fluctuating price and supply of fish meal (FM). This study evaluated the growth performance, feed stability, blood biochemistry, and liver and gut morphology of Betta splendens using BSFL as an alternative to FM. Five formulated diets were prepared: 0% BSFL, 6.5% BSFL, 13% BSFL, 19.5% BSFL, and 24.5% BSFL. The expansion rate, pellet durability index, floatability, bulk density, and water stability of the prepared feed have been assessed. Except for the diameter of the feed, all the parameters studied differed significantly (
p
<
0.05
) across the experimental diets. After 60 days, the fish fed with 13% BSFL had the highest final length, final weight, net weight gain, specific growth rate, weight gain, and gastrointestinal weight, with mean and standard deviation values of
3.97
±
0.43
cm,
3.95
±
0.1
g,
2.78
±
0.1
g,
4.63
±
0.17
,
4.65
±
0.13
,
237.26
±
7.9
%
, and
0.04
±
0.01
mg, respectively. Similar blood haematology and biochemical properties, including corpuscular volume, lymphocytes, white blood cells, red blood cells, haematocrit, albumin, and alkaline phosphatase, were the highest (
p
<
0.05
) in the 13% BSFL diet group compared to the other treatment groups. In addition, BSFL had a significant impact (
p
<
0.05
) on villus length, width, and crypt depth for the anterior and posterior guts of B. splendens. The 13% BSFL diet group had an intact epithelial barrier in the goblet cell arrangement and a well-organized villus structure and tunica muscularis, compared to the other treatment groups. Furthermore, the liver cell was altered with different BSFL inclusions; the 13% FM group demonstrated better nuclei and cytoplasm structure than the other treatment groups. In conclusion, replacing 13% FM with BSFL could improve the growth performance, blood parameters, and liver and intestine morphology of B. splendens, thus providing a promising alternative diet for ornamental freshwater fish
The ChoCO-W prospective observational global study: Does COVID-19 increase gangrenous cholecystitis?
No full textBACKGROUND: The incidence of the highly morbid and potentially lethal gangrenous cholecystitis was reportedly increased during the COVID-19 pandemic. The aim of the ChoCO-W study was to compare the clinical findings and outcomes of acute cholecystitis in patients who had COVID-19 disease with those who did not. METHODS: Data were prospectively collected over 6 months (October 1, 2020, to April 30, 2021) with 1-month follow-up. In October 2020, Delta variant of SARS CoV-2 was isolated for the first time. Demographic and clinical data were analyzed and reported according to the STROBE guidelines. Baseline characteristics and clinical outcomes of patients who had COVID-19 were compared with those who did not. RESULTS: A total of 2893 patients, from 42 countries, 218 centers, involved, with a median age of 61.3 (SD: 17.39) years were prospectively enrolled in this study; 1481 (51%) patients were males. One hundred and eighty (6.9%) patients were COVID-19 positive, while 2412 (93.1%) were negative. Concomitant preexisting diseases including cardiovascular diseases (p < 0.0001), diabetes (p < 0.0001), and severe chronic obstructive airway disease (p = 0.005) were significantly more frequent in the COVID-19 group. Markers of sepsis severity including ARDS (p < 0.0001), PIPAS score (p < 0.0001), WSES sepsis score (p < 0.0001), qSOFA (p < 0.0001), and Tokyo classification of severity of acute cholecystitis (p < 0.0001) were significantly higher in the COVID-19 group. The COVID-19 group had significantly higher postoperative complications (32.2% compared with 11.7%, p < 0.0001), longer mean hospital stay (13.21 compared with 6.51 days, p < 0.0001), and mortality rate (13.4% compared with 1.7%, p < 0.0001). The incidence of gangrenous cholecystitis was doubled in the COVID-19 group (40.7% compared with 22.3%). The mean wall thickness of the gallbladder was significantly higher in the COVID-19 group [6.32 (SD: 2.44) mm compared with 5.4 (SD: 3.45) mm; p < 0.0001]. CONCLUSIONS: The incidence of gangrenous cholecystitis is higher in COVID patients compared with non-COVID patients admitted to the emergency department with acute cholecystitis. Gangrenous cholecystitis in COVID patients is associated with high-grade Clavien-Dindo postoperative complications, longer hospital stay and higher mortality rate. The open cholecystectomy rate is higher in COVID compared with non -COVID patients. It is recommended to delay the surgical treatment in COVID patients, when it is possible, to decrease morbidity and mortality rates. COVID-19 infection and gangrenous cholecystistis are not absolute contraindications to perform laparoscopic cholecystectomy, in a case by case evaluation, in expert hands
Timing of surgery following SARS‐CoV‐2 infection: an international prospective cohort study
No full textPeri‐operative SARS‐CoV‐2 infection increases postoperative mortality. The aim of this study was to determine the optimal duration of planned delay before surgery in patients who have had SARS‐CoV‐2 infection. This international, multicentre, prospective cohort study included patients undergoing elective or emergency surgery during October 2020. Surgical patients with pre‐operative SARS‐CoV‐2 infection were compared with those without previous SARS‐CoV‐2 infection. The primary outcome measure was 30‐day postoperative mortality. Logistic regression models were used to calculate adjusted 30‐day mortality rates stratified by time from diagnosis of SARS‐CoV‐2 infection to surgery. Among 140,231 patients (116 countries), 3127 patients (2.2%) had a pre‐operative SARS‐CoV‐2 diagnosis. Adjusted 30‐day mortality in patients without SARS‐CoV‐2 infection was 1.5% (95%CI 1.4–1.5). In patients with a pre‐operative SARS‐CoV‐2 diagnosis, mortality was increased in patients having surgery within 0–2 weeks, 3–4 weeks and 5–6 weeks of the diagnosis (odds ratio (95%CI) 4.1% (3.3–4.8), 3.9% (2.6–5.1) and 3.6% (2.0–5.2), respectively). Surgery performed ≥ 7 weeks after SARS‐CoV‐2 diagnosis was associated with a similar mortality risk to baseline (odds ratio (95%CI) 1.5% (0.9–2.1%)). After a ≥ 7 week delay in undertaking surgery following SARS‐CoV‐2 infection, patients with ongoing symptoms had a higher mortality than patients whose symptoms had resolved or who had been asymptomatic (6.0% (95%CI 3.2–8.7) vs. 2.4% (95%CI 1.4–3.4) vs. 1.3% (95%CI 0.6–2.0%), respectively). Where possible, surgery should be delayed for at least 7 weeks following SARS‐CoV‐2 infection. Patients with ongoing symptoms ≥ 7 weeks from diagnosis may benefit from further delay
