First record of Aspicera hartigi (Hymenoptera, Figitidae) from India, with observations on its foraging behavior on Ephedra plants

Zubair Ahmad Rather,Aijaz Ahmad Wachkoo,Anzar Ahmad Khuroo,Abdul Rashid Dar,Tanvir-Ul-Hassan Dar 국립중앙과학관 2019 Journal of Asia-Pacific Biodiversity Vol.12 No.3

Aspicera hartigi Dalla Torre, 1889 is reported for the first time from India. A brief diagnosis and photographic illustrations of the species are provided to validate this new faunal record for India from the Kashmir valley in Western Himalaya. In addition, the present study for the first time reports the feeding of Aspicera hartigi on the pollination drop of the female cones in Ephedra plants, which provides novel insights about its foraging behavior and hint toward its role as pollination drop robber.

Epidemiologic Data, Tumor Size, Histologic Tumor Type and Grade, Pathologic Staging and Follow Up in Cancers of the Ampullary Region and Head of Pancreas in 311 Whipple Resection Specimens of Pakistani Patients

Ahmad, Zubair,Ud Din, Nasir,Minhas, Khurram,Moeen, Sarosh,Ahmed, Arsalan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.17

Aim: To report the histologic findings on Whipple resection specimens and thus determine the extent and spread of carcinomas of ampullary region and head of pancreas in our population. Setting: Section of Histopathology, Department of Pathology, Aga Khan University Hospital (AKUH), Karachi, Pakistan. Materials and Methods: A case series of 311 consecutive Whipple resection specimens received between January 1,2003 and December 31, 2014. Specimens processed for histologic sections and representative sections submitted and histologically examined as per established and standard protocols. All relevant tumor parameters including histologic type, histologic grade, pathologic T and N stage and tumor size were assessed. Epidemiologic data were also recorded. All findings were analysed using SPSS 19.0 software. Results: Ampullary (periampullary) carcinomas were much more common than carcinomas of the head of the pancreas, especially in males, with an average age of 53 years. Mean tumor size was 2.5 cms, over 54% were well differentiated. A large majority were pT2 or pT3 and N0. Carcinomas of pancreatic head were also more common in males, mean age was 55 years, mean tumor size was 3.5cms, and over 65% were moderately differentiated. The majority were T2 or T3 and pN1. Prognostically, significant statistical correlation was seen with tumor grade and pathologic T and N stage (p values statistically significant). However, tumor size was not statistically significant. Conclusions: Ampullary carcinomas are more common compared to pancreatic carcinomas. Majority of ampullary carcinomas were well differentiated while majority of pancreatic carcinomas were moderately differentiated. Large majority of both types of cases were pT2 or T3. Histologic tumor grade and pathologic T and N stage are significantly related to prognosis in Pakistani patients with ampullary and pancreatic cancers.

Trustworthy Mutual Attestation Protocol for Local True Single Sign-On System: Proof of Concept and Performance Evaluation

( Zubair Ahmad Khattak ),( Jamalul-lail Ab Manan ),( Suziah Sulaiman ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.9

In a traditional Single Sign-On (SSO) scheme, the user and the Service Providers (SPs) have given their trust to the Identity Provider (IdP) or Authentication Service Provider (ASP) for the authentication and correct assertion. However, we still need a better solution for the local/ native true SSO to gain user confidence, whereby the trusted entity must play the role of the ASP between distinct SPs. This technical gap has been filled by Trusted Computing (TC), where the remote attestation approach introduced by the Trusted Computing Group (TCG) is to attest whether the remote platform integrity is indeed trusted or not. In this paper, we demonstrate a Trustworthy Mutual Attestation (TMutualA) protocol as a proof of concept implementation for a local true SSO using the Integrity Measurement Architecture (IMA) with the Trusted Platform Module (TPM). In our proposed protocol, firstly, the user and SP platform integrity are checked (i.e., hardware and software integrity state verification) before allowing access to a protected resource sited at the SP and releasing a user authentication token to the SP. We evaluated the performance of the proposed TMutualA protocol, in particular, the client and server attestation time and the round trip of the mutual attestation time.

Central, Extraventricular and Atypical Neurocytomas: a Clinicopathologic Study of 35 Cases from Pakistan Plus a Detailed Review of the Published Literature

Ahmad, Zubair,Din, Nasir Ud,Memon, Aisha,Tariq, Mohammad Usman,Idrees, Romana,Hasan, Sheema Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Background: Central neurocytomas are rare neuronal neoplasms with a favorable prognosis. They are typically located in the lateral ventricles of the brain and mostly histologically correspond to WHO grade II with a Mib 1 labelling index of <2%. Similar tumors located in the cerebral hemispheres and spinal cord, for example, are called "extraventricular neurocytomas". A few tumors histologically show atypia, mitoses, vascular proliferation and/or necrosis and a Mib 1 index >2 % and are designated as "atypical neurocytomas. Aim: The aim of our study was to describe the common as well as unusual morphologic features and the role of various immunohistochemical stains in the diagnosis of these rare tumors. Materials and Methods: We retrieved and reviewed 35 cases diagnosed between 2001 and 2015. Results: Sixty percent of patients were males, and the mean age was 26 years. 31 cases (88.6%) were intraventricular and 4(11.4%) were extraventricular. Histologically, 6 cases (17.1%) were compatible with "atypical neurocytomas". All cases showed the classic morphology comprising nests and sheets of uniform, round cells with uniform round to oval nuclei with finely speckled chromatin and perinuclear cytoplasmic clearing (halos). All cases also showed delicate, fibrillary, neuropil-like matrices. Other common histologic features included capillary-sized blood vessels in a branching pattern in 57.1%, foci of calcification in 34.3% and perivascular pseudorosettes in 20%. Rare findings included Homer-Wright or true rosettes in 8.6% and ganglioid cells in 2.9%. Synaptophysin was the most consistent and valuable marker, being positive in almost all cases. GFAP positivity in tumor cells was seen in 25.7% of cases. Follow up was available in 13 patients. Of these 9 had histologically typical and 4 had atypical tumors. Only 1 (with an atypical neurocytoma) died, probably due to complications of surgery within one month, while 12 (including 3 with atypical neurocytomas) remained alive. Recurrence developed in 1 of these 12 patients (histologically consistent with typical morphology) almost 9 years after surgery. Only 4 patients, including 2 with atypical tumors, received postoperative radiotherapy, all with surgery in 2010 or later. Overall, prognosis was excellent with prolonged, recurrence free survival and most patients, even without receiving radiation therapy, were alive and well for many years, even a decade or more after surgery, without developing any recurrence, indicating the benign nature of these neoplasms.

Errors in Surgical Pathology Reports: a Study from a Major Center in Pakistan

Ahmad, Zubair,Idrees, Romana,Uddin, Nasir,Ahmed, Arsalan,Fatima, Saira Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.4

Background: Errors in surgical pathology diagnosis can have serious consequences for the patient. Since the final product of a surgical pathology lab is the report, errors can be picked by reviewing reports of cases. Aim: To determine the frequency and types of error in surgical pathology reports of cases signed out in 2014 in a laboratory in Karachi, Pakistan. Materials and Methods: All surgical pathology reports in which changes were made in the original report after sign out and an amended report was issued were included. Errors included: (1) misinterpretations; (2) missing critical information; (3) erroneous critical information; (4) misidentification; and (5) typographic errors. Results: Errors were identified in 210 cases (0.37%). These comprised 199 formalin fixed specimens and 11 frozen sections. The latter represented 3.8% of a total of 2,170 frozen sections. Of the 11 frozen section errors, 10 were misinterpretations. Of the 199 permanent specimens, 99 (49.7%) were misinterpretations, 65 (32.7%) belonged to missing critical information category, 8 (4%) belonged to erroneous critical information category, 8(4%) were misidentifications, 16(8%) were typographic errors while 3 cases (1.5%) were other errors. Most misinterpretations occurred in the gastro intestinal, liver and pancreato biliary tract (23.2%) and breast (13.1%). Another 87 cases were reviewed on the clinicians' request. However diagnosis after review remained the same as the original diagnosis. In 49 out of these (56.3%), additional workup was performed at the time of the review. Conclusions: Our findings were similar to other published studies. We need to develop documented procedures for timely review of cases to detect errors.

THE LOGARITHMIC KUMARASWAMY FAMILY OF DISTRIBUTIONS: PROPERTIES AND APPLICATIONS

Ahmad, Zubair Korean Mathematical Society 2019 대한수학회논문집 Vol.34 No.4

In this article, a new family of lifetime distributions by adding two additional parameters is introduced. The new family is called, the logarithmic Kumaraswamy family of distributions. For the proposed family, explicit expressions for some mathematical properties are derived. Maximum likelihood estimates of the model parameters are also obtained. This method is applied to develop a new lifetime model, called the logarithmic Kumaraswamy Weibull distribution. The proposed model is very flexible and capable of modeling data with increasing, decreasing, unimodal or modified unimodal shaped hazard rates. To access the behavior of the model parameters, a simulation study has been carried out. Finally, the potentiality of the new method is proved via analyzing two real data sets.

A new extended alpha power transformed family of distributions: properties, characterizations and an application to a data set in the insurance sciences

Ahmad, Zubair,Mahmoudi, Eisa,Hamedani, G.G. The Korean Statistical Society 2021 Communications for statistical applications and me Vol.28 No.1

Heavy tailed distributions are useful for modeling actuarial and financial risk management problems. Actuaries often search for finding distributions that provide the best fit to heavy tailed data sets. In the present work, we introduce a new class of heavy tailed distributions of a special sub-model of the proposed family, called a new extended alpha power transformed Weibull distribution, useful for modeling heavy tailed data sets. Mathematical properties along with certain characterizations of the proposed distribution are presented. Maximum likelihood estimates of the model parameters are obtained. A simulation study is provided to evaluate the performance of the maximum likelihood estimators. Actuarial measures such as Value at Risk and Tail Value at Risk are also calculated. Further, a simulation study based on the actuarial measures is done. Finally, an application of the proposed model to a heavy tailed data set is presented. The proposed distribution is compared with some well-known (i) two-parameter models, (ii) three-parameter models and (iii) four-parameter models.

Rhabdomyosarcoma - an Epidemiological and Histopathologic Study of 277 Cases from a Major Tertiary Care Center in Karachi, Pakistan

Ahmad, Zubair,Din, Nasir Ud,Ahmad, Arsalan,Imran, Sheharbano,Pervez, Shahid,Ahmed, Rashida,Kayani, Naila Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.2

Aim: To present the epidemiologic data (age, gender, size etc) and histopathologic and immunohistochemical features of cases of rhabdomyosarcoma (RMS) reported in our department. Settings: Section of Histopathology, Department of Pathology and Microbiology, Aga Khan University Hospital, Karachi, Pakistan. Duration: All cases of RMS diagnosed between January 1, 2003 and December 31, 2012 were included in the study. Results: A total of 277 cases were included. Embryonal rhabdomyosarcoma (ERMS) was by far the dominant histologic type (87.4%) followed by alveolar type (ARMS)(9.4%). ERMS was much more common in males (64.0%)and over 65% of cases occurred in the first decade of life (over 90% in the first two decades). Head and neck region was commonest site for ERMS (46.7%), followed by the genitourinary system (16.1%). Over 65% cases of ARMS occurred in the extremities. Over 80% cases of ARMS occurred in the first 3 decades of life. Immunohistochemical staining for Desmin and MyoD1 was positive in 96.7% and 85.4% respectively. Conclusions: The epidemiologic data and microscopic findings in our patients are similar to international published data on rhabdomyosarcoma.

How Our Practice of Histopathology, Especially Tumour Pathology has Changed in the Last Two Decades: Reflections from a Major Referral Center in Pakistan

Ahmad, Zubair,Idrees, Romana,Fatima, Saira,Arshad, Huma,Din, Nasir-Ud,Memon, Aisha,Minhas, Khurram,Ahmed, Arsalan,Fatima, Syeda Samia,Arif, Muhammad,Ahmed, Rashida,Haroon, Saroona,Pervez, Shahid,Hassa Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.9

Continued advances in the field of histo pathology (and cyto pathology) over the past two decades have resulted in dramatic changes in the manner in which these disciplines are now practiced. This is especially true in the setting of a large university hospital where the role of pathologists as clinicians (diagnosticians), undergraduate and postgraduate educators, and researchers has evolved considerably. The world around us has changed significantly during this period bringing about a considerable change in our lifestyles and the way we live. This is the world of the internet and the world-wide web, the world of Google and Wikipedia, of Youtube and Facebook where anyone can obtain any information one desires at the push of a button. The practice of histo (and cyto) pathology has also evolved in line with these changes. For those practicing this discipline in a poor, developing country these changes have been breathtaking. This is an attempt to document these changes as experienced by histo (and cyto) pathologists practicing in the biggest center for Histopathology in Pakistan, a developing country in South Asia with a large (180 million) and ever growing population. The Section of Histopathology, Department of Pathology and Microbiology at the Aga Khan University Hospital (AKUH) in Karachi, Pakistan's largest city has since its inception in the mid-1980s transformed the way histopathology is practiced in Pakistan by incorporating modern methods and rescuing histopathology in Pakistan from the primitive and outdated groove in which it was stuck for decades. It set histopathology in Pakistan firmly on the path of modernity and change which are essential for better patient management and care through accurate and complete diagnosis and more recently prognostic and predictive information as well.

Commonest Cancers in Pakistan - Findings and Histopathological Perspective from a Premier Surgical Pathology Center in Pakistan

Ahmad, Zubair,Idrees, Romana,Fatima, Saira,Uddin, Nasir,Ahmed, Arsalan,Minhas, Khurram,Memon, Aisha,Fatima, Syeda Samia,Arif, Muhammad,Hasan, Sheema,Ahmed, Rashida,Pervez, Shahid,Kayani, Naila Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Context: There are no recent authoritative data about incidence and prevalence of various types of cancers in Pakistan. Aim: To determine the frequency of malignant tumors seen in our practice and provide a foundation for building a comprehensive cancer care strategy. Materials and Methods: 10,000 successive cases of solid malignant tumors reported in 2014 were included. All cases had formalin fixed, paraffin embedded specimens available and diagnosis was based on histological examination of H&E stained slides plus ancillary studies at the Section of Histopathology, Department of Pathology and Laboratory Medicine, Aga Khan University Hospital, Karachi. The latest WHO classifications were used along with the latest CAP protocols for reporting and the most updated TNM staging. Results: There were 9,492 (94.9%) primary tumors while 508 (5.1%) were metastatic. Some 5,153 (51.5%) were diagnosed in females and 4,847 (48.5%) in males. The commonest malignant tumors in females were breast (32%), esophagus (7%), lymphomas (6.8%), oral cavity (6.7%) and ovary (4.8%), while in males they were oral cavity (13.9%), lymphomas (12.8%), colorectum (7.9%), stomach (6.9%) and esophagus (6.6%). Malignant tumors were most common in the 5th, 6th and 7th decades. About 8% were seen under 20 years of age. Conclusions: Oral cavity and gastrointestinal cancers continue to be extremely common in both genders. Breast and esophageal cancers are prevalent in females. Lung and prostate cancer are less common than in the west. Ovarian cancer was very common but cervix cancer was less so.