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Light slowing and all-optical time division multiplexing of hybrid four-wave mixing signal in nitrogen-vacancy center

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Chinese Physics B 2020年第5期29卷 254-259页

作者： Ruimin Wang irfan ahmed Faizan Raza Changbiao Li Yanpeng Zhang School of Science&Key Laboratory for Physical Electronics and Devices of the Ministry of Education&Shaanxi Key Laboratory of Information Photonic Technique Xi’an Jiaotong UniversityXi’an 710049China Department of Physics City University of Hong KongKowloonHong Kong SARChina Electrical Engineering Department Sukkur IBA University65200SindhPakistan

We report the experimental results of hybrid four-wave mixing and fluorescence signals from nitrogen-vacancy(NV)centers in diamond. The fluorescence signals are slowed owing to dark state. The observed delay time of light slowing due to interconversion between NV^- and NV^0 is about 6.4 μs. The relative intensities of read-out signals change with the wavelength and power of writing pulse. Based on light slowing, we present the model of all-optical time division multiplexing. The intensity ratio in different demultiplexed channels is modulated by the wavelength and power of control field. It has potential applications in quantum communication and all-optical network.

关键词： nonlinear optics fluorescence time division multiplexing

National guidelines for the diagnosis and treatment of hilar cholangiocarcinoma

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World Journal of Gastroenterology 2024年第9期30卷 1018-1042页

作者： Faisal Saud Dar Zaigham Abbas irfan ahmed Muhammad Atique Usman Iqbal Aujla Muhammad Azeemuddin Zeba Aziz Abu Bakar Hafeez Bhatti Tariq Ali Bangash Amna Subhan Butt Osama Tariq Butt Abdul Wahab Dogar Javed Iqbal Farooqi Faisal Hanif Jahanzaib Haider Siraj Haider Syed Mujahid Hassan Adnan Abdul Jabbar Aman Nawaz Khan Muhammad Shoaib Khan Muhammad Yasir Khan Amer Latif Nasir Hassan Luck Ahmad Karim Malik Kamran Rashid Sohail Rashid Mohammad Salih Abdullah Saeed Amjad Salamat Ghias-un-Nabi Tayyab Aasim Yusuf Haseeb Haider Zia Ammara Naveed Department of Hepatopancreatic Biliary Surgery&Liver Transplant Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Hepatogastroenterology and Liver Transplantation Dr.Ziauddin University HospitalKarachi 75600SindhPakistan University of Aberdeen Aberdeen B243FXUnited Kingdom Department of Pathology Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Gastroenterology&Hepatology Pakistan Kidney and Liver Institute&Research CentreLahore 54000Pakistan Department of Radiology Aga Khan UniversityKarachi 74800Pakistan Department of Oncology Hameed Latif HospitalLahore 54000Pakistan Division of Hepatopancreatic Biliary Surgery&Liver Transplantation Shifa International HospitalIslamabad 44000Pakistan Department of Hepatopancreatic Biliary Surgery&Liver Transplant Shaikh Zayed Hospital and Post Graduate Medical InstituteLahore 54000Pakistan Department of Medicine Aga Khan University HospitalKarachi 74800Pakistan Department of Liver Transplant Pir Abdul Qadir Shah Jeelani Institute of Medical SciencesGambat 66020Pakistan Department of Medicine&Gastroenterology Lifecare Hospital and Research CentrePeshawar 25000Khyber PakhtunkhwaPakistan Department of Hepatopancreatobiliary&Liver Transplant Bahria International HospitalLahore 54000Pakistan Department of Surgery Hepatopancreatobiliary&Liver TransplantDow University of Health SciencesKarachi 74800Pakistan Department of Gastroenterology Hepatology&NutritionPir Abdul Qadir Shah Jeelani Institute of Medical SciencesGambat 66020Pakistan Department of Oncology Dr.Ziauddin HospitalKarachi 74800Pakistan Department of Radiology Rehman Medical InstitutePeshawar 25000Pakistan Army Liver Transplant Unit Pak Emirates Military HospitalRawalpindi 46000Pakistan Department of Gastroenterology Sindh Institute of Urology and TransplantationKarachi 75500Pakistan Rashid Nursing Home and Cancer Clinic Rashid Nursing Home and Cancer ClinicRawalpindi 46000Pakistan Department of Gastroentero

A consensus meeting of national experts from all major national hepatobiliary centres in the country was held on May 26,2023,at the Pakistan Kidney and Liver Institute&Research Centre(PKLI&RC)after initial consultations with the *** Pakistan Society for the Study of Liver Diseases(PSSLD)and PKLI&RC jointly organised this *** effort was based on a comprehensive literature review to establish national practice guidelines for hilar cholangiocarcinoma(hCCA).The consensus was that hCCA is a complex disease and requires a multidisciplinary team approach to best manage these *** coordinated effort can minimise delays and give patients a chance for curative treatment and effective *** diagnostic and staging workup includes high-quality computed tomography,magnetic resonance imaging,and magnetic resonance *** cytology or biopsy utilizing endoscopic retrograde cholangiopancreatography is a mainstay for ***,histopathologic confirmation is not always required before *** ultrasound with fine needle aspiration of regional lymph nodes and positron emission tomography scan are valuable adjuncts for *** only curative treatment is the surgical resection of the biliary tree based on the Bismuth-Corlette *** patients with unresectable hCCA can be considered for liver *** chemotherapy should be offered to patients with a high risk of *** use of preoperative biliary drainage and the need for portal vein embolisation should be based on local multidisciplinary *** with acute cholangitis can be drained with endoscopic or percutaneous biliary *** chemotherapy with cisplatin and gemcitabine has shown improved survival in patients with irresectable and recurrent hCCA.

关键词： Hilar cholangiocarcinoma Bismuth-Corlette classification Memorial Sloan Kettering Cancer Centre Staging Preoperative biliary drainage Portal vein embolisation Surgical resection Hepatectomy

Performance analysis of a random ARQ initialized cooperative communication protocol in shadowed Nakagami-m wireless channel

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Science in China(Series F) 2009年第6期52卷 1027-1036页

作者： ahmed irfan PENG MuGen WANG WenBo SHAH Syed Ismail Wireless Signal Processing and Network Laboratory Beijing University of Posts and Telecommunications Real-Time MIMO Test-Bed Laboratory Iqra University Islamabad Pakistan

In this paper, we develop and analyze an energy efficient ARQ （automatic repeat request） initialized transmit diversity protocol for cooperative *** access control （MAC） layer packet retransmission limit （similar to aShortRetryLimit or aLongRetryLimit [802.11-1997]） has been used as an actuator for transmit cooperative diversity *** take the channel state information （CSI） as a function of retransmission tries and the number of retransmission tries is modeled as a random *** close to the source node are chosen for the transmit *** form expressions are obtained for symbol error rate （SER）, outage capacity and outage probability for the proposed scheme in shadowed fading *** cooperative scheme achieves lower signal-to-noise ratio （SNR）, stumpy outage probability, higher bandwidth, and transmit energy efficiencies for desired average symbol error rate （ASER） than the preceding ARQ based cooperative ***, the results of computer simulations are included to demonstrate the efficacy of the proposed scheme and to verify the accuracy of the analytical expressions.

关键词： automatic repeat request (ARQ) cooperative transmit diversity composite shadowed fading channel wireless networks

Current practice of anticoagulant in the treatment of splanchnic vein thrombosis secondary to acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2020年第2期19卷 116-121页

作者： William Norton Gabija Lazaraviciute George Ramsay Irene Kreis irfan ahmed Mohamed Bekheit Department of General Surgery Aberdeen Royal InfirmaryAberdeen AB252ZNUK Rowett Institute of Nutrition and Health University of AberdeenForesterhillAberdeen AB252ZDUK Clinical Effectiveness Unit Royal College of Surgeons of England35-43 Lincoln’s Inn FieldsHolbornLondon WC2A 3PEUK Department of Surgery El Kabbary HospitalEl KabbaryAlexandriaEgypt

Background:Severe acute pancreatitis is a common diagnosis in emergency general surgery and can be a cause of significant morbidity and mortality.A consequence of severe acute pancreatitis is thrombus in the splanchnic *** thrombi can potentially lead to bowel ischemia or hepatic ***,another complication of severe acute pancreatitis is retroperitoneal *** this time,it is unclear if treating patients for splanchnic vein thrombosis in the context of severe acute pancreatitis is associated with any outcome benefit.A systematic review might clarify this *** sources:A two-fold search strategy(one broad and one precise)looked at all published *** review was registered on PROSPERO(ID:CRD42018102705).MEDLINE,EMBASE,PubMed,Cochrane and Web of Science databases were searched and potentially relevant papers were reviewed indepen-dently by two *** disagreement was reviewed by a third independent *** outcome was reestablishment of flow in the thrombosed vein versus bleeding ***:Of 1462 papers assessed,a total of 16 papers were eligible for *** were no ran-domized controlled trials,2 were case series,5 retrospective single-center studies and 9 case *** were a total of 198 patients in these studies of whom 92(46.5%)received anticoagulation *** rates of recanalization of veins in the treated and non-treated groups was 14%and 11%and bleeding complications were 16%and 5%,***,the included studies were too heterogeneous to undertake a ***:The systematic review highlights the lack evidence addressing this clinical ***-fore a randomized controlled trial would be appropriate to undertake.

关键词： Severe acute pancreatitis Splanchnic vein thrombosis Anticoagulant therapy

Cartesian Product Based Transfer Learning Implementation for Brain Tumor Classification

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Computers, Materials & Continua 2022年第11期73卷 4369-4392页

作者： irfan ahmed Usmani Muhammad Tahir Qadri Razia Zia Asif Aziz Farheen Saeed Electronic Engineering Department Sir Syed University of Engineering&TechnologyKarachi75300Pakistan Department of Computer Science Bahria University Karachi CampusKarachi75260Pakistan Christus Trinity Clinic TexasUSA

Knowledge-based transfer learning techniques have shown good performance for brain tumor classification,especially with small ***,to obtain an optimized model for targeted brain tumor classification,it is challenging to select a pre-trained deep learning(DL)model,optimal values of hyperparameters,and optimization algorithm(solver).This paper first presents a brief review of recent literature related to brain tumor ***,a robust framework for implementing the transfer learning technique is *** the proposed framework,a Cartesian product matrix is generated to determine the optimal values of the two important hyperparameters:batch size and learning *** extensive exercise consisting of 435 simulations for 11 state-of-the-art pre-trained DL models was performed using 16 paired hyperparameters from the Cartesian product matrix to input the model with the three most popular solvers(stochastic gradient descent with momentum(SGDM),adaptive moment estimation(ADAM),and root mean squared propagation(RMSProp)).The 16 pairs were formed using individual hyperparameter values taken from literature,which generally addressed only one hyperparameter for optimization,rather than making a grid for a particular *** proposed framework was assessed using a multi-class publicly available dataset consisting of glioma,meningioma,and pituitary *** assessment shows that ResNet18 outperforms all other models in terms of accuracy,precision,specificity,and recall(sensitivity).The results are also compared with existing state-of-the-art research work that used the same *** comparison was mainly based on performance metric“accuracy”with support of three other parameters“precision,”“recall,”and“specificity.”The comparison shows that the transfer learning technique,implemented through our proposed framework for brain tumor classification,outperformed all existing *** the best of our knowledge,the proposed framework is a

关键词： Deep transfer learning Cartesian product hyperparameter optimization magnetic resonance imaging(MRI) brain tumor classification

Field evaluation of some bait additives against Indian crested porcupine(Hystrix indica)(Rodentia:Hystricidae)

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Integrative Zoology 2013年第3期8卷 285-292页

作者： Muhammad MUSHTAQ Iftikhar HUSSAIN Afsar MIAN Shahid MUNIR irfan ahmed Abdul Aziz KHAN Department of Zoology PMAS Arid Agriculture UniversityRawalpindiPakistan Wildlife Management PMAS Arid Agriculture UniversityRawalpindiPakistan National Agricultural Research Centre IslamabadPakistan

This research study evaluated the effect of different additives on the bait consumption by Indian crested porcupine,a serious forest and agricultural pest,under field *** additives(saccharin,common salt,bone meal,fish meal,peanut butter,egg yolk,egg shell powder,yeast powder,mineral oil and coconut oil)at 2 and 5%each were tested for their relative preference,using groundnut-maize(1:1)as basic *** the additives were tested under a no-choice test *** control tests,no additive was mixed with the basic *** at 5%concentration significantly enhanced the consumption of bait over the basic bait,while 2%saccharin supplemented bait resulted in a non-significant bait *** other additives did not enhance the consumption of the bait material;rather,these worked as ***,the repellency was lowest with the common salt,followed by egg yolk,egg shell powder,bone meal,peanut butter,mineral oil,fish meal and yeast powder,while coconut remained the most repellent *** present study suggested that groundnut-maize(1:1)supplemented with 5%saccharin was the preferred bait combination,and can be used with different rodenticides for the management of Indian crested porcupine.

关键词： additives baits evaluation Hystrix indica Indian crested porcupine

The role of graft reperfusion sequence in the development of non-anastomotic biliary strictures following orthotopic liver transplantation: A meta-analysis

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Hepatobiliary & Pancreatic Diseases International 2019年第1期18卷 4-11页

作者： Mohamed Bekheit Matteo Catanzano Stuart Shand irfan ahmed ELSaid ELKayal Gihan Mohamed Shehata Adel Zaki Center of Liver Surgery and Transplantation Paul Brousse Hospital University of Paris-Sud Medical Research Institute University of Alexandria HPB Surgery Unit Department of Surgery Aberdeen Royal Infirmary Department of Surgery Elkabbary General Hospital University of Aberdeen Department of Surgery Alexandria Main University Hospital Faculty of Medicine

Background: Liver transplant is a potential cure for liver failure and hepatic malignancy but there are many techniques which have been described for vascular reconstruction. This study was to compare the prevalence of non-anastomotic biliary stricture and other surgical complications based on Clavien-Dindo scoring system, in initial portal reperfusion(sequential) versus simultaneous or initial artery reperfusion. Data sources: Meta-analysis of published studies comparing the outcomes of both techniques was carried out. Data search was conducted across the major databases and studies were selected under the guidance of the Cochrane guidelines for systematic reviews and meta-analysis. Results: Seven studies were included to address the primary and the secondary outcomes. No statistical difference was found in the incidence of non-anastomotic biliary strictures(OR = 0.40; P = 0.14), regardless of reperfusion technique. The pooled estimate of the Clavien-Dindo grading of complications was not significantly different between the techniques, though Clavien-Dindo II complications were higher in the simultaneous or initial artery reperfusion group than the initial portal reperfusion group(OR = 2.73; P = 0.01). Similarly, there was no difference in the operative time, hospital stay and other outcomes addressed in this report. Conclusions: The available evidence suggests that there is no significant difference demonstrated in the rate of non-anastomotic biliary strictures or other complications, between the two techniques, except for Clavien-Dindo II complications.

关键词： Liver transplantation Organ transplantation Liver surgery Rejection

Forecasting investment and consumption behavior of economic agents through dynamic computable general equilibrium model

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Financial Innovation 2018年第1期4卷 125-145页

作者： irfan ahmed Claudio Socci Francesca Severini Qaiser Rafique Yasser Rosita Pretaroli Preston University No.85Street 3Sector H-8/1MacerataPakistan University of Macerata MacerataItaly.

Much research has been devoted to examination of the financial easing policy of the European Central Bank(ECB).However,this study is one of the first to use a dynamic micro-founded model to investigate empirically the impact of the ECB’s Quantitative Easing(QE)policy on consumption and investment by economic agents in Italy(households,government,firms,and the rest of the world).For this purpose,we constructed a Financial Social Accounting Matrix(FSAM)for the Italian economy for the year 2009 to calibrate a dynamic computable general equilibrium model(DCGE).This model allowed us to evaluate the direct and indirect impact of money flow on the behavior of consumption and *** findings of the study confirmed the positive impact of the ECB’s monetary policy on the level of investment and consumption.

关键词： European Central Bank Quantitative easing Monetary policy Investment behavior Social accounting matrix Dynamic CGE analysis

Knowledge Driven Paper Recommendation Using Heterogeneous Network Embedding Method

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Journal of Computer and Communications 2018年第12期6卷 157-170页

作者： irfan ahmed Zubair ahmed Kalhoro Department of Computer Science and Engineering Southeast University Nanjing China Institute of Mathematics and Computer Science University of Sindh Jamshoro Pakistan

We search a variety of things over the Internet in our daily lives, and numerous search engines are available to get us more relevant results. With the rapid technological advancement, the internet has become a major source of obtaining information. Further, the advent of the Web2.0 era has led to an increased interaction between the user and the website. It has become challenging to provide information to users as per their interests. Because of copyright restrictions, most of existing research studies are confronting the lack of availability of the content of candidates recommending articles. The content of such articles is not always available freely and hence leads to inadequate recommendation results. Moreover, various research studies base recommendation on user profiles. Therefore, their recommendation needs a significant number of registered users in the system. In recent years, research work proves that Knowledge graphs have yielded better in generating quality recommendation results and alleviating sparsity and cold start issues. Network embedding techniques try to learn high quality feature vectors automatically from network structures, enabling vector-based measurers of node relatedness. Keeping the strength of Network embedding techniques, the proposed citation-based recommendation approach makes use of heterogeneous network embedding in generating recommendation results. The novelty of this paper is in exploiting the performance of a network embedding approach i.e., matapath2vec to generate paper recommendations. Unlike existing approaches, the proposed method has the capability of learning low-dimensional latent representation of nodes (i.e., research papers) in a network. We apply metapath2vec on a knowledge network built by the ACL Anthology Network (all about NLP) and use the node relatedness to generate item (research article) recommendations.

关键词： Network Embedding Heterogeneous Representation Learning Paper-Citation Relations Recommender System Learning Latent Representations