1
|
Naylor K, Chiriaco G, Uddin A, Williamson E, Ralph D, Sangster P. Does implementing a new protocol for the induction of the spermatogenesis pathway in Klinefelter patients result in improved sperm retrieval? Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00723-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
|
2
|
Dutta A, Rahman M, Ghosh A, Hasan T, Uddin A. Prevalence and Associated Risk Factors of Postpartum Anestrus in Dairy Cows of Sylhet District, Bangladesh. AJVS 2023. [DOI: 10.5455/ajvs.48060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The objectives of current study were to assess the prevalence and risk factors associated with postpartum anestrus in lactating dairy cows in Sylhet region, Bangladesh. A total of 420 postpartum cows of different breed and age were selected randomly from different dairy farms in studied area. Structured questionnaire was used to collect data from farm owner on prevalence and risk factors for postpartum anestrus. Observed heat within 60 days after parturition was considered as normal cyclic cows and others were considered as postpartum anestrus. The prevalence of postpartum anestrus was 36.20%. The study shows that older cows take relatively more time for ovarian resumption. Cow’s having first parity shows cyclicity within 60 days of parturition, and postpartum anestrus increases significantly with the advancement of parity. Postpartum anestrus was significantly higher (P< 0.001) in cows with poor (≤1.0) and excessive (>3) body condition scores (BCS), respectively, compared to those with moderate/optimal BCS (2–3). The postpartum cyclicity in cows within 60 days with a history of normal placental expulsion was significantly higher than in the cows with RFM. Ovarian cyclicity was highest (75.92%) among the cows that were maintained in adequate hygienic conditions and lowest (43.51%) in a poor environment. The highest percentage (88.10%) of cows showed postpartum cyclicity with a history of short lactation length (0-150 days) and resumption of postpartum estrous cycle increases significantly with lactation length. Resumption of postpartum estrus cycles in cows takes more time with a history of minimal (<15 liters) daily milk production than the cow with medium (>15-25 liters) daily milk production. Cows get an adequate feed supply (both concentrate and green grass), which shows a positive effect on postpartum cyclicity. Pre and postpartum complications have a significant (p<0.001) effect on the postpartum cyclicity of cows. Endometritis (81.25%) followed by pyometra (75.76%) were recorded as major reproductive obstacles in ovarian resumption, whereas uterine prolapse (70.59%) followed by abortion (61.54%), milk fever (58.33%), stillbirth (58.33%) and dystocia (57.63%) were the major recorded complications in post-partum phase. The study also revealed that the non-restricted suckling period has a significant (p<0.001) negative effect on ovarian resumption. The risk factors including parity, BCS, placental expulsion, hygienic condition, lactation length, daily milk production and management system were significantly (P<0.01) influenced the postpartum cyclicity. Maintaining optimal BCS of cows, proper hygienic and good management practice, and farmer's training on management of cattle reproduction would improve the number of cows for breeding by 60 days postpartum.
Collapse
|
3
|
Uddin A, Pratap H, Jha G, Vinoo A, Subbiah P, Sahni D, Win MM, Kuttuva S, Korde V, Eldolify M, Abualsaud S. 778 Portfolio for Core Surgical Training: International Doctors’ Experience. Br J Surg 2022. [DOI: 10.1093/bjs/znac269.407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Abstract
Introduction
As the number of international medical graduates (IMG) applying for Core Surgical Training (CST) is growing, the understanding of the portfolio and application system is crucial to succeeding in this competitive application process. We conducted a webinar to grow the awareness of the system, especially amongst doctors still in the process of moving to the UK for surgical training.
Method
The webinar was part of an online teaching series for IMG doctors run by the SSID society. It was conducted in two separate two-hour sessions using a virtual conferencing tool in September and October 2021. Alongside, it was streamed on Facebook live to grow the reach. The advertising was done via flyers on social media and various WhatsApp groups. Each webinar was delivered by an IMG doctor in CST in the UK where they shared their personal experiences. Feedback was collected after each webinar using an online form generating tool and analysed on Excel. The certificate of attendance was distributed via E-mail.
Results
The webinar was viewed by 1200 on Facebook Live. Feedback was received from 66 attendees. 96.96% agreed that the webinar improved their understanding of the portfolio and 94.45% agreed they learned about ways to improve their portfolio. 89.39% agreed that they would change their practice after attending this webinar.
Conclusions
Simple online webinars can improve the understanding of the portfolio requirements for CST amongst IMG doctors. Subsequently, this could allow for early portfolio preparation opportunities, improve application self-assessment scores, and reduce the years needed to get a successful training number.
Collapse
Affiliation(s)
- A Uddin
- Morriston Hospital , Wales Deanery, Swansea , United Kingdom
| | - H Pratap
- Royal Bolton Hospital , Northwest Deanery, Bolton , United Kingdom
| | - G Jha
- Queen's Hospital, Barking, Havering and Redbridge University Hospitals NHS Trust , London , United Kingdom
| | - A Vinoo
- Mid and South Essex NHS Foundation Trust , Basildon , United Kingdom
| | - P Subbiah
- Sussex University Hospitals NHS Foundation Trust , Sussex , United Kingdom
| | - D Sahni
- Sheffield Teaching Hospital , Sheffield , United Kingdom
| | - MM Win
- Nottingham University Hospitals NHS Trust , East Midlands Deanery, Nottingham , United Kingdom
| | - S Kuttuva
- Newcaste upon Tyne Hospitals NHS Foundation Trust , Newcastle , United Kingdom
| | - V Korde
- Royal Derby Hospital , Derby , United Kingdom
| | - M Eldolify
- Nottingham University Hospitals NHS Trust , Nottingham , United Kingdom
| | - S Abualsaud
- Royal Hallamshire Hospital , Sheffield , United Kingdom
| |
Collapse
|
4
|
Fisher R, Hadjittofi C, Ali Z, Antonas P, Parekh K, Seraj S, Thomas L, Uddin A, Lovett B. 755 Elective Surgery in the COVID-19 Pandemic: Outcomes of 100 Consecutive Cases. Br J Surg 2021. [PMCID: PMC8135925 DOI: 10.1093/bjs/znab134.083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Introduction The COVID-19 pandemic halted elective surgical activity. Basildon University Hospital established an elective Green Zone for COVID-19 swab negative patients who isolated for 14 days. This study reviewed the outcomes of the first 100 patients. Method A single-centre study was performed. Demographic and perioperative electronic data were supplemented with telephone follow-up for the first 100 Green Zone patients and analysed in Microsoft Excel. Results One hundred Green Zone patients underwent surgery between 21/05/2020 and 16/06/2020. The median age was 55 (14-88) years. 52% were female. Their operations were performed by General Surgery (39%), Gynaecology (17%), Vascular Surgery (14%), Oral Surgery (12%), ENT (9%), Urology (8%), and Pain Management (1%). Preoperatively, 100% had a negative SARS-CoV-2 swab and one had CT evidence of mild resolving COVID-19. Two patients had postoperative SARS-CoV-2 swabs, both negative. Median length of stay was 0 (0-7) days. 84% responded to telephone follow-up at a median 25 (13-54) postoperative days, 69% of whom were asymptomatic There were no 30-day major complications (>Clavien-Dindo IIIa) or 90-day mortality. Conclusions Elective surgery can be safe during the COVID-19 pandemic, with appropriate measures in place. This has significant implications in the context of an ever-expanding NHS waiting list during a pandemic of uncertain duration.
Collapse
Affiliation(s)
- R Fisher
- Basildon University Hospital, Basildon, United Kingdom
| | - C Hadjittofi
- Basildon University Hospital, Basildon, United Kingdom
| | - Z Ali
- Basildon University Hospital, Basildon, United Kingdom
| | - P Antonas
- Basildon University Hospital, Basildon, United Kingdom
| | - K Parekh
- Basildon University Hospital, Basildon, United Kingdom
| | - S Seraj
- Basildon University Hospital, Basildon, United Kingdom
| | - L Thomas
- Basildon University Hospital, Basildon, United Kingdom
| | - A Uddin
- Basildon University Hospital, Basildon, United Kingdom
| | - B Lovett
- Basildon University Hospital, Basildon, United Kingdom
| |
Collapse
|
5
|
Uddin A, Hadjittofi C, Lovett B. 691 Audit of Drug Chart Completion in General Surgery. Br J Surg 2021. [DOI: 10.1093/bjs/znab134.470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Introduction
The accuracy of drug charts is crucial for good clinical practice. The General Medical Council states, doctors must keep clear, accurate and legible records, also applying to prescriptions. This audit quantified the accuracy of drug chart completion in a General Surgery Department within a District General Hospital.
Method
Single-centre retrospective assessment of drug charts in November 2019, assigning binary outcomes to each domain: “100% complete” (all details such as drug name, dose, unit, route, frequency, indication, duration, signatures) vs. “incomplete”. After analysis (Microsoft Excel/IBM SPSS v.24), results were circulated locally, followed by re-audit during June-August 2020.
Results
Comparison of audit (n = 22) vs. re-audit (n = 25) drug charts across 17 domains demonstrated higher completion rates for 7 domains: Alerts/allergies (4/22:18% vs. 18/25:72%; p < 0.001), signatures (2/22:9% vs. 17/25:68%; p < 0.001), venous thromboembolism risk assessment (5/22:24% vs. 24/25:96%; p < 0.001), antithrombotic (0/21 vs. 9/25:36%; p = 0.002), regular (1/22:5% vs. 10/25:40%; p = 0.04), as-required (0/21 vs. 5/22:23%; p = 0.020) medication and intravenous fluids (1/16:6% vs. 20/21:95%; p < 0.001). Performance in 10 domains was not significantly different (p ≥ 0.05).
Conclusions
Standard documents like drug charts may appear accurate at first glance. However, when assessed with strict criteria, performance is suboptimal. Simple, cost-effective educational interventions can significantly improve accuracy, with positive implications for patient safety.
Collapse
|
6
|
Hadjittofi C, Seraj SS, Uddin A, Ali ZJ, Antonas PL, Fisher RJ, Parekh KP, Lovett B, Ahmad A. Laparoscopic vs open surgery during the COVID-19 pandemic: what are the risks? Ann R Coll Surg Engl 2021; 103:354-359. [PMID: 33682443 DOI: 10.1308/rcsann.2020.7067] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
INTRODUCTION The initial intercollegiate surgical guidance from the UK during the COVID-19 pandemic resulted in significant changes to practice. Avoidance of laparoscopy was recommended, to reduce aerosol generation and risk of virus transmission. Evidence on the safety profile of laparoscopy during the pandemic is lacking. This study compares patient outcomes and risk to staff from laparoscopic and open gastrointestinal operations during the COVID-19 pandemic. METHODS Single-centre retrospective study of gastrointestinal operations performed during the peak of the COVID-19 pandemic. Demographic, comorbidity, perioperative and survival data were collected from electronic medical records and supplemented with patient symptoms reported at telephone follow up. Outcomes assessed were: patient mortality, illness among staff, patient COVID-19 rates, length of hospital stay and postdischarge symptomatology. RESULTS A total of 73 patients with median age of 56 years were included; 55 (75%) and 18 (25%) underwent laparoscopic and open surgery, respectively. All-cause mortality was 5% (4/73), was related to COVID-19 in all cases, with no mortality after laparoscopic surgery. A total of 14 staff members developed COVID-19 symptoms within 2 weeks, with no significant difference between laparoscopic and open surgery (10 vs 4; p=0.331). Median length of stay was shorter in the laparoscopic versus the open group (4.5 vs 9.9 days; p=0.011), and postdischarge symptomatology across 15 symptoms was similar between groups (p=0.135-0.814). CONCLUSIONS With appropriate protective measures, laparoscopic surgery is safe for patients and staff during the COVID-19 pandemic. The laparoscopic approach maintains an advantage of shorter length of hospital stay compared with open surgery.
Collapse
Affiliation(s)
- C Hadjittofi
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - S S Seraj
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - A Uddin
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - Z J Ali
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - P L Antonas
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - R J Fisher
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - K P Parekh
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - B Lovett
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| | - A Ahmad
- Basildon and Thurrock University Hospitals NHS Foundation Trust, UK
| |
Collapse
|
7
|
Abstract
The SRY gene is present within the sex-determining region of the Y chromosome which is responsible for maleness in mammals. The nonuniform usage of synonymous codons in the mRNA transcript for encoding a particular amino acid is the codon usage bias (CUB). Analysis of codon usage pattern is important to understand the genetic and molecular organisation of a gene. It also helps in heterologous gene expression, design of primer and synthetic gene. However, the analysis of codon usage bias of SRY gene was not yet studied. We have used bioinformatic tools to analyse codon usage bias of SRY gene across mammals. Codon bias index (CBI) indicated that the overall extent of codon usage bias was weak. The relative synonymous codon usage (RSCU) analysis suggested that most frequently used codons had an A or C at the third codon position. Compositional constraint played an important role in codon usage pattern as evident from correspondence analysis (CA). Significant correlation among nucleotides constraints indicated that both mutation pressure and natural selection affect the codon usage pattern. Neutrality plot suggested that natural selection might play a major role, while mutation pressure might play a minor role in codon usage pattern in SRY gene in different species of mammals.
Collapse
Affiliation(s)
- M N Choudhury
- Department of Biotechnology, Assam University, Silchar, Assam, India
| | - A Uddin
- Department of Zoology, Moinul Hoque Choudhury Memorial Science College, Algapur, Hailakandi, India
| | - S Chakraborty
- Department of Biotechnology, Assam University, Silchar, Assam, India
| |
Collapse
|
8
|
Meena P, Uddin A, Tripathi M, Paswan V. In Vitro Fermentation and Methane Production with Diets of Varying Roughage (Prosopis cineraria leaves) to Concentrate Ratio. ANIM NUTR FEED TECHN 2017. [DOI: 10.5958/0974-181x.2017.00018.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
9
|
Knowles R, Laxton V, Caine E, Verran A, Uddin A, Hartley R, Wade M, Galliver M, Rahman A. 7DELIRIUM: DIAGNOSIS, PREVENTION AND MANAGEMENT. A MULTIDISCIPLINARY PROBLEM WITH A MULTIDISCIPLINARY SOLUTION. Age Ageing 2016. [DOI: 10.1093/ageing/afw024.07] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
10
|
Khatun R, Ahmed S, Hasan MA, Islam MN, Uddin A, Mahmud M. A Baseline Survey on Cattle Imports through Different Peripheral Areas of Bangladesh. ACTA ACUST UNITED AC 2016. [DOI: 10.9734/ajea/2016/27486] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
11
|
Musa TA, Uddin A, Fairbairn TA, Dobson LE, Steadman C, Kidambi A, Motwani M, Ripley DP, McDiarmid AK, Swoboda P, Erhayiem B, Garg P, Sourbron S, Plein S, McCann G, Greenwood JP. 21 Left atrial remodelling following treatment of symptomatic severe aortic stenosis. Heart 2015. [DOI: 10.1136/heartjnl-2015-307845.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
12
|
Musa TA, Uddin A, Fairbairn TA, Dobson LE, Steadman C, Kidambi A, Motwani M, Ripley DP, McDiarmid AK, Swoboda P, Erhayiem B, Garg P, Sourbron S, Plein S, McCann G, Greenwood JP. 22 Surgical aortic valve replacement (SAVR) upon right ventricular function: a cardiac mri study: Abstract 22 Table 1. Heart 2015. [DOI: 10.1136/heartjnl-2015-307845.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
13
|
Kidambi A, Motwani M, Uddin A, Ripley DP, McDiarmid AK, Swoboda PP, Broadbent DA, Musa TA, Erhayiem B, Greenwood JP, Plein S. 20 Myocardial extracellular volume predicts functional recovery in acute myocardial infarction more accurately than threshold-based measures of late gadolinium enhancement transmural extent. Heart 2015. [DOI: 10.1136/heartjnl-2015-307845.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
14
|
Hasan M, Mamun A, Uddin A, Hassan M, Hasan M, Rahman M. Investigation into gyneco-pathological disorders and identification of associated bacteria from the genital organs of cows in Dinajpur, Bangladesh. J Adv Vet Anim Res 2015. [DOI: 10.5455/javar.2015.b76] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
|
15
|
Kidambi A, Mather AN, Motwani M, Swoboda P, Uddin A, Greenwood JP, Plein S. Contractile recovery of infarct zone in reperfused acute myocardial infarction is influenced by microvascular obstruction and intramyocardial hemorrhage. Eur Heart J 2013. [DOI: 10.1093/eurheartj/eht308.p2043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
16
|
Plein S, Kidambi A, Sourbron S, Maredia N, Uddin A, Motwani M, Ripley DP, Herzog B, Brown JMB, Nixon J, Everett CC, Greenwood JP. 097 FACTORS ASSOCIATED WITH FALSE NEGATIVE CARDIOVASCULAR MAGNETIC RESONANCE PERFUSION STUDIES: A CE-MARC SUBSTUDY. Heart 2013. [DOI: 10.1136/heartjnl-2013-304019.97] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
17
|
Kidambi A, Mather AN, Uddin A, Motwani M, Ripley DP, Herzog B, Gunn J, Plein S, Greenwood JP. 093 RECIPROCAL ECG CHANGE IN ST-ELEVATION MYOCARDIAL INFARCTION IS ASSOCIATED WITH AREA AT RISK AND MYOCARDIAL SALVAGE FOLLOWING REVASCULARIZATION. Heart 2013. [DOI: 10.1136/heartjnl-2013-304019.93] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
18
|
Kidambi A, Mather AN, Motwani M, Swoboda P, Uddin A, Greenwood JP, Plein S. 092 MICROVASCULAR OBSTRUCTION AND INTRAMYOCARDIAL HAEMORRHAGE INFLUENCES INFARCT ZONE CONTRACTILE RECOVERY IN REPERFUSED ACUTE MYOCARDIAL INFARCTION. Heart 2013. [DOI: 10.1136/heartjnl-2013-304019.92] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
19
|
Ripley DP, Higgins D, McDiarmid AK, Bainbridge GJ, Uddin A, Kidambi A, Herzog B, Greenwood JP, Plein S. 1064Heart Rate Adaptive Maximal Resolution Cardiovascular
Magnetic Resonance Myocardial Stress Perfusion Imaging at 3.0T. Eur Heart J Cardiovasc Imaging 2013. [DOI: 10.1093/ehjci/jet070ct] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|
20
|
Uddin A, Yemenicioglu S, Chen CH, Corigliano E, Milaninia K, Theogarajan L. Integration of solid-state nanopores in a 0.5 μm CMOS foundry process. Nanotechnology 2013; 24:155501. [PMID: 23519330 PMCID: PMC3672232 DOI: 10.1088/0957-4484/24/15/155501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
High-bandwidth and low-noise nanopore sensor and detection electronics are crucial in achieving single-DNA-base resolution. A potential way to accomplish this goal is to integrate solid-state nanopores within a CMOS platform, in close proximity to the biasing electrodes and custom-designed amplifier electronics. Here we report the integration of solid-state nanopore devices in a commercial complementary metal-oxide-semiconductor (CMOS) potentiostat chip implemented in On-Semiconductor's 0.5 μm technology. Nanopore membranes incorporating electrodes are fabricated by post-CMOS micromachining utilizing the n+ polysilicon/SiO2/n+ polysilicon capacitor structure available in the aforementioned process. Nanopores are created in the CMOS process by drilling in a transmission electron microscope and shrinking by atomic layer deposition. We also describe a batch fabrication method to process a large of number of electrode-embedded nanopores with sub-10 nm diameter across CMOS-compatible wafers by electron beam lithography and atomic layer deposition. The CMOS-compatibility of our fabrication process is verified by testing the electrical functionality of on-chip circuitry. We observe high current leakage with the CMOS nanopore devices due to the ionic diffusion through the SiO2 membrane. To prevent this leakage, we coat the membrane with Al2O3, which acts as an efficient diffusion barrier against alkali ions. The resulting nanopore devices also exhibit higher robustness and lower 1/f noise as compared to SiO2 and SiNx. Furthermore, we propose a theoretical model for our low-capacitance CMOS nanopore devices, showing good agreement with the experimental value. In addition, experiments and theoretical models of translocation studies are presented using 48.5 kbp λ-DNA in order to prove the functionality of on-chip pores coated with Al2O3.
Collapse
|
21
|
Jayaraman V, Cole G, Robertson M, Burgner C, John D, Uddin A, Cable A. Rapidly swept, ultra-widely-tunable 1060 nm MEMS-VCSELs. Electron Lett 2012; 48:1331-1333. [PMID: 23520409 PMCID: PMC3601947 DOI: 10.1049/el.2012.3180] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Demonstrated are 1060 nm microelectromechanical-systems-based tunable vertical-cavity surface-emitting lasers (MEMS-VCSELs) with a 100 nm continuous tuning range under repetitively scanned operation at rates beyond 500 kHz and a 90 nm continuous tuning range under static operation. These devices employ a thin strained InGaAs multiple quantum well active region integrated with a fully oxidised GaAs/AlxOy bottom mirror and a suspended dielectric top mirror. The devices are optically pumped via 850 nm light. These ultra-widely tunable lasers represent the first MEMS-VCSELs reported in this wavelength range, and are ideally suited for application in ophthalmic swept-source optical coherence tomography.
Collapse
Affiliation(s)
- V. Jayaraman
- Praevium Research Inc., 5266 Hollister Avenue, Suite 224, Santa Barbara, CA 93111, USA
| | - G.D. Cole
- Advanced Optical Microsystems, 1243 West El Camino Real, Mountain View, CA 94040, USA
| | - M. Robertson
- Praevium Research Inc., 5266 Hollister Avenue, Suite 224, Santa Barbara, CA 93111, USA
| | - C. Burgner
- Praevium Research Inc., 5266 Hollister Avenue, Suite 224, Santa Barbara, CA 93111, USA
| | - D. John
- Praevium Research Inc., 5266 Hollister Avenue, Suite 224, Santa Barbara, CA 93111, USA
| | - A. Uddin
- Praevium Research Inc., 5266 Hollister Avenue, Suite 224, Santa Barbara, CA 93111, USA
| | - A. Cable
- Thorlabs, 56 Sparta Ave, Newton, NJ 07860, USA
| |
Collapse
|
22
|
Uddin A, Wong HS, Teo CC. CdSe/ZnS quantum dot size dependent carrier relaxation in hybrid organic/inorganic system. J Nanosci Nanotechnol 2012; 12:7853-7859. [PMID: 23421148 DOI: 10.1166/jnn.2012.6615] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We have studied the CdSe/ZnS quantum dot (QD) size dependent carrier relaxation dynamics in hybrid organic/inorganic system for the first time. The QD size was from 5.0 to 2.0 nm. The optical narrow emission of quantum dots shift to higher energies as the size of dots gets smaller due to the 3-D confinement which splits the continuous band into a series of discrete quantum states and increases the band gap. The carrier relaxation time in QDs was found to increases as the pump power increased and reached saturation at approximately 326 microW excitation, probably due to the saturation of traps with the photoexcited charge carriers within individual nanoparticles. The relaxation rate was also increased with pump power, indicating that new relaxation processes e.g., Auger processes and faster carrier trapping were present. The slow decay component remained at the lowest power (51microW) excitation with no fast decay present. The decrease of CdSe/ZnS QD size increased the fast component relaxation rate probably due to a higher number of surface defects hence inducing faster trapping of carriers by shallow trap state.
Collapse
Affiliation(s)
- A Uddin
- School of Photovoltaic and Renewable Energy Engineering, The University of New South Wales, Sydney, 2052, Australia
| | | | | |
Collapse
|
23
|
Abstract
We have designed a high efficiency organic solar cell with light trapping structure on transference cylindrical substrate. An electrical and optical simulation of the light trapping structure has been performed on the basis of finite element and transfer matrix formalism methods. Absorption spectrum, internal quantum efficiency, external quantum efficiency, maximum power output and efficiency of the organic solar cell are simulated and presented in terms of three variables: the height, diameter of the glass substrate and the thickness of the organic active layer. The efficiency of the proposed organic solar cell with light trapping structure is enhanced by a factor of 2 than the similar structure on the flat plain glass substrate. The optimum organic active layer thickness to achieve the highest efficiency is shifted from 65 to 20 nm. Finally, we have investigated the effect of light incident angle on the performance of the proposed cell structure.
Collapse
Affiliation(s)
- L Song
- School of Photovoltaic and Renewable Energy Engineering, the University of New South Wales, Sydney, Australia
| | | |
Collapse
|
24
|
Jayaraman V, Cole GD, Robertson M, Uddin A, Cable A. High-sweep-rate 1310 nm MEMS-VCSEL with 150 nm continuous tuning range. Electron Lett 2012; 48:867-869. [PMID: 23976788 PMCID: PMC3749789 DOI: 10.1049/el.2012.1552] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Microelectromechanical-systems-based vertical-cavity surface-emitting lasers (MEMS-VCSELs) capable of a 150 nm continuous tuning range near 1310 nm are demonstrated. These devices employ a thin optically pumped active region structure with large free-spectral range, which promotes wide and continuous tuning. To achieve VCSEL emission at 1310 nm, a wide-gain-bandwidth indium phosphide-based multiple quantum well active region is combined with a wide-bandwidth fully oxidised GaAs-based mirror through wafer bonding, with tuning enabled by a suspended dielectric top mirror. These devices are capable of being scanned over the entire tuning range at frequencies up to 500 kHz, making them ideal for applications such as swept source optical coherence tomography and high-speed transient spectroscopy.
Collapse
Affiliation(s)
- V Jayaraman
- Praevium Research, Inc., 5266 Hollister Avenue, Suite 224, Santa Barbara, CA 93111, USA
| | | | | | | | | |
Collapse
|
25
|
Skinner HJ, Mahmoud A, Uddin A, Mathew T. An investigation into the causes of unexpected intra-operative transoesophageal echocardiography findings*. Anaesthesia 2012; 67:355-60. [DOI: 10.1111/j.1365-2044.2011.07022.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
26
|
Uddin A, Teo CC. Effects of QD concentrations and thermal annealing on the performance of self-assembly QD-OLEDs. J Nanosci Nanotechnol 2011; 11:10610-10614. [PMID: 22408958 DOI: 10.1166/jnn.2011.4083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We have fabricated and investigated the effect of CdSe/ZnS quantum dot (QD) concentrations on the performance of self-assembly hybrid inorganic/organic light emitting diodes (QD-OLEDs). The uniform distribution of QDs with controllable density was achieved using the conventional spin-coating method. There was a QD threshold concentration for the emission of QDs in QD-OLED. Below that threshold concentration we did not observe the QD emission from the QD-OLED. The best performance of QD-OLED was found for the QD concentration of -9 x 10(11) cm(-2). The QD electroluminescence intensity was increased about three times after the annealing of QD-OLED at 80 degrees C for about 20 minutes in nitrogen atmosphere. The QD electroluminescence peak energy was remain same before and after the annealing of QD-OLED. The maximum external quantum efficiency was around 2.1%. The effect of process parameters and the QD emission mechanism are discussed.
Collapse
Affiliation(s)
- A Uddin
- School of Photovoltaic and Renewable Energy Engineering, The University of New South Wales, Sydney 2052, Australia
| | | |
Collapse
|
27
|
Bevc S, Hojs R, Ekart R, Gorenjak M, Puklavec L, Nakano C, Hamano T, Fujii N, Matsui I, Obi Y, Okada N, Tsubakihara Y, Rakugi H, Isaka Y, Pisano A, Testa A, Spoto B, Sanguedolce MC, Parlongo RM, Tripepi G, Leonardis D, Mallamaci F, Zoccali C, Papale M, Gigante M, Prattichizzo C, Rocchetti MT, Battaglia M, Gesualdo L, Ranieri E, Legendre C, Babu S, Furman R, Sheerin N, Cohen D, Gaber O, Eitner F, Delmas Y, Loirat C, Greenbaum L, Bedrosian C, Zimmerhackl LB, Gane E, Deray G, Piratvisuth T, Chan HLY, Zeuzem S, Jia J, Ren H, Uddin A, Bosset S, Avila C, Trylesinski A. CKD / Human studies. Clin Kidney J 2011. [DOI: 10.1093/ndtplus/4.s2.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
28
|
|
29
|
Abstract
We report an unusual case of primary vasculitis presenting with unilateral submandibular gland enlargement and lymphadenopathy resulting in stridor.
Collapse
Affiliation(s)
- A Uddin
- Department of Nephrology, John Walls Renal Unit, Leicester General Hospital, Leicester, UK
| | | | | |
Collapse
|
30
|
Shamsudduha M, Uddin A, Saunders JA, Lee MK. Quaternary stratigraphy, sediment characteristics and geochemistry of arsenic-contaminated alluvial aquifers in the Ganges-Brahmaputra floodplain in central Bangladesh. J Contam Hydrol 2008; 99:112-36. [PMID: 18502538 DOI: 10.1016/j.jconhyd.2008.03.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2007] [Revised: 03/25/2008] [Accepted: 03/31/2008] [Indexed: 05/13/2023]
Abstract
This study focuses on the Quaternary stratigraphy, sediment composition, mineralogy, and geochemistry of arsenic (As)-contaminated alluvial aquifers in the Ganges-Brahmaputra floodplain in the central Bangladesh. Arsenic concentrations in 85 tubewells in Manikganj area, 70 km northwest of Dhaka City, range from 0.25 microg/L to 191 microg/L with a mean concentration of 33 microg/L. Groundwater is mainly Ca-HCO(3) type with high concentrations of dissolved As, Fe, and Mn, but low level of SO(4). The uppermost aquifer occurs between 10 m and 80 m below the surface that has a mean arsenic concentration of 35 microg/L. Deeper aquifer (>100 m depth) has a mean arsenic concentration of 18 microg/L. Sediments in the upper aquifer are mostly gray to dark-gray, whereas sediments in the deep aquifer are mostly yellowing-gray to brown. Quartz, feldspar, mica, hornblende, garnet, kyanite, tourmaline, magnetite, ilmenite are the major minerals in sediments from both aquifers. Biotite and potassium feldspar are dominant in shallow aquifer, although plagioclase feldspar and garnet are abundant in deep aquifer sediments. Sediment composition suggests a mixed provenance with sediment supplies from both orogenic belts and cratons. High arsenic concentrations in sediments are found within the upper 50 m in drilled core samples. Statistical analysis shows that As, Fe, Mn, Ca, and P are strongly correlated in sediments. Concentrations of Cd, Cu, Ni, Zn, and Bi also show strong correlations with arsenic in the Manikganj sediment cores. Authigenic goethite concretions, possibly formed by bacteria, are found in the shallow sediments, which contain arsenic of a concentration as high as 8.8 mg/kg. High arsenic concentrations in aquifers are associated with fine-grained sediments that were derived mostly from the recycled orogens and relatively rapidly deposited mainly by meandering channels during the Early to Middle Holocene rising sea-level conditions.
Collapse
Affiliation(s)
- M Shamsudduha
- Department of Geology and Geography, Auburn University, Auburn, AL 36849, USA
| | | | | | | |
Collapse
|
31
|
Akhanda AH, Quayum MA, Uddin A, Ahmed N, Uddin T, Ahmed T. Herpes zoster ophthalmicus in an otherwise healthy 7 years child. Mymensingh Med J 2007; 16:221-4. [PMID: 17703164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A 07 years otherwise healthy child, non vaccinated for chickenpox and with a history of chickenpox infection at 02 years of age presented with red colored lesions in right upper lid, right side of forehead, vertex and right side of nose and defective vision in right eye in Mymensingh Medical College Hospital, 20 days after the appearance of blister in the same region. On examination granulation tissue was present on the same area. There was no hair and skin over that area. Lesion was strictly limited to right side of midline. Eyelashes of right upper lid were absent and there was defective closure of eyelids. Best corrected visual acuity of right eye was 3/60 and of left eye was 6/6. There was ciliary congestion of right eye with haziness of cornea at interpalpebral region of right eye. Corneal sensitivity was reduced and there was uniform fluorescein staining at central part of cornea. Mild flare and cells were present in anterior chamber. Fundus examination revealed no abnormality. He was treated with systemic acyclovir, antibiotics, topical acyclovir, antibiotic and atropine. Corneal ulcer and skin lesions were healed, but the patient developed cicatricial ectropion of right upper lid and best corrected visual acuity of right eye was reduced to 6/60 due to corneal opacity. So early diagnosis and treatment of herpes zoster ophthalmicus is mandatory to prevent sight threatening complications.
Collapse
Affiliation(s)
- A H Akhanda
- Department of Ophthalmology, Mymensingh Medical College, Mymensingh, Bangladesh
| | | | | | | | | | | |
Collapse
|
32
|
Rahman M, Uddin A, Das GC, Akanda NI. A giant vesical calculus. Mymensingh Med J 2007; 16:S57-S59. [PMID: 17917633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Massive or giant vesical calculus is a rare entity in the recent urological practice. Males are affected more than the females. Vesical calculi are usually secondary to bladder outlet obstruction. These patients present with recurrent urinary tract infection, haematuria or with retention of urine. We report a young male patient who presented with defaecatory problems along with other urinary symptoms. The patient having an average built, non diabetic but hypertensive. The stone could be palpated by physical examination. His urea levels were within normal limits but urine examination shows infection. USG reveals bilateral hydronephrosis with multiple stones in both kidneys along with a giant vesical calculus. After controlling urinary infection and hypertention he underwent an open cystolithotomy. During operation digital rectal help was needed to remove the stone as it was adherent with bladder mucosa. Post operative period was uneventful. His urinary output was quite normal and had no defaecatory problems. Patient left the hospital 10 days after operation.
Collapse
Affiliation(s)
- M Rahman
- General Hospital, Jamalpur, Bangladesh
| | | | | | | |
Collapse
|
33
|
Uddin A, Bennett M, Nayeem K, Marren P, Abushaira H. A case of papular mycosis fungoides: new clinical variant of early mycosis fungoides. J Eur Acad Dermatol Venereol 2007; 21:685-7. [PMID: 17447987 DOI: 10.1111/j.1468-3083.2006.01983.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
34
|
Abstract
Samples of cortical bone, derived from human femur, have been studied using terahertz time-domain transmission spectroscopy. The relationship between the broadband THz parameters and the previously acquired values of Young's modulus and x-ray attenuation (CT number), and the density of each bone sample, is investigated. The only significant correlation is that between THz transmission and sample density, suggesting that the potential use of THz radiation as a non-invasive probe of bone quality is limited. The spectra of absorption coefficient and refractive index are plotted over the frequency range 0.1-1.25 THz. There is evidence that the sample hydration state is a factor in the resultant THz parameters.
Collapse
Affiliation(s)
- M R Stringer
- Institute of Microwaves and Photonics, School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK
| | | | | | | | | | | | | |
Collapse
|
35
|
Attwood TK, Bradley P, Flower DR, Gaulton A, Maudling N, Mitchell AL, Moulton G, Nordle A, Paine K, Taylor P, Uddin A, Zygouri C. PRINTS and its automatic supplement, prePRINTS. Nucleic Acids Res 2003; 31:400-2. [PMID: 12520033 PMCID: PMC165477 DOI: 10.1093/nar/gkg030] [Citation(s) in RCA: 299] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The PRINTS database houses a collection of protein fingerprints. These may be used to assign uncharacterised sequences to known families and hence to infer tentative functions. The September 2002 release (version 36.0) includes 1800 fingerprints, encoding approximately 11 000 motifs, covering a range of globular and membrane proteins, modular polypeptides and so on. In addition to its continued steady growth, we report here the development of an automatic supplement, prePRINTS, designed to increase the coverage of the resource and reduce some of the manual burdens inherent in its maintenance. The databases are accessible for interrogation and searching at http://www.bioinf.man.ac.uk/dbbrowser/PRINTS/.
Collapse
Affiliation(s)
- T K Attwood
- School of Biological Sciences and Department of Computer Science, The University of Manchester, Manchester M13 9PT, UK.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Uddin A, Nakata H, Otsuka E. Impact ionization of free excitons in stressed pure germanium. Phys Rev B Condens Matter 1990; 41:3078-3081. [PMID: 9994080 DOI: 10.1103/physrevb.41.3078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
37
|
Uddin A, Nakata H, Otsuka E. Off-equilibrium population of holes in the stress-split valence bands in photoexcited silicon and germanium. Phys Rev B Condens Matter 1990; 41:3752-3760. [PMID: 9994178 DOI: 10.1103/physrevb.41.3752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
|
38
|
Andersson TG, Chen ZG, Kulakovskii VD, Uddin A, Vallin JT. Photoluminescence and photoconductivity measurements on band-edge offsets in strained molecular-beam-epitaxy-grown InxGa. Phys Rev B Condens Matter 1988; 37:4032-4038. [PMID: 9945037 DOI: 10.1103/physrevb.37.4032] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
|
39
|
Laycock N, Hartlein M, Uddin A. Manual ferrozine method for serum iron and total iron-binding capacity adapted to a computer-directed analyzer, the Gilford 3500. Clin Chem 1980. [DOI: 10.1093/clinchem/26.11.1625a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
40
|
Laycock N, Hartlein M, Uddin A. Manual ferrozine method for serum iron and total iron-binding capacity adapted to a computer-directed analyzer, the Gilford 3500. Clin Chem 1980; 26:1625-6. [PMID: 7418215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|