Journal of the Society for Information Display, 2008
This paper demonstrates the first substrate-free cholesteric liquid-crystal displays. The encapsu... more This paper demonstrates the first substrate-free cholesteric liquid-crystal displays. The encapsulated cholesteric displays are ultra-thin (with a total thickness around 20 µm) and ultra-lightweight (0.002 g/cm 2). The displays exhibit unprecedented conformability, flexibility, and drapability while maintaining electro-optical performance and mechanical integrity. All functional display layers are sequentially coated on a preparation substrate and then lifted-off from the preparation substrate to form a free-standing display. The display fabrication process, electro-optical performance, and display flexibility are discussed.
We present a flexible touch‐sensitive writing tablet utilizing a reflective bistable cholesteric ... more We present a flexible touch‐sensitive writing tablet utilizing a reflective bistable cholesteric liquid crystal laminated between two conductive‐polymer coated polyethylene‐terephthalate substrates. The device features a selective pressure response suitable for high‐resolution ...
Bistable reflective cholesteric displays are a liquid crystal display technology developed to fil... more Bistable reflective cholesteric displays are a liquid crystal display technology developed to fill a market need for very low power displays. Their unique look, high reflectivity, bistability, and simple structure make them an ideal flat panel display choice for handheld or other ...
Journal of the Society for Information Display, 2005
Bistable reflective cholesteric liquid‐crystal displays are low‐power displays that are suitable ... more Bistable reflective cholesteric liquid‐crystal displays are low‐power displays that are suitable for a variety of applications ranging from signage to high‐resolution electronic books. Recent advancements have included higher brightness, full color, black and white from a single ...
Journal of the Society for Information Display, 2009
A novel optically addressable, flexible bistable cholesteric liquid-crystal display (ChLCD) is pr... more A novel optically addressable, flexible bistable cholesteric liquid-crystal display (ChLCD) is presented. These displays utilize azo-binaphthalene photosensitive chiral dopants that undergo photo-isomerization upon exposure to light. The isomerization results in a change in the pitch of the cholesteric liquid crystal (ChLC), which enables the creation of inherently high-resolution lightweight displays that are optically written. The displays can be photo-addressed without patterned electrodes or complex addressing schemes. Capitalizing on the dynamic pitch and the bistability of photosensitive ChLCDs, the display is switched with a single pulse at a specific single voltage to drive the region of the display with a shorter pitch to the focal-conic texture and the region of the display with a longer pitch to the planar texture. Once in the different textures, the display can hold an image indefinitely regardless of ambient lighting. As such, these displays are a natural fit for badges, shelf-labels, and point-of-sale cards. In this paper, the photosensitive properties of an encapsulated display system in comparison to an unencapsulated display system is discussed. Properties such a photosensitivity, thermal relaxation, and electro-optical response are studied and reported. In addition, a flexible optically addressable ChLCD is developed and demonstrated.
Flexible, reflective, bistable displays have become the focus of significant research over the pa... more Flexible, reflective, bistable displays have become the focus of significant research over the past decade due to their appeal for alternative applications requiring low power, small form factor, and flexibility. Some of the first flexible displays to be offered in the market are non-traditional Reflex TM displays in unique and exciting new applications, such as, writing tablets, electronic skins, and smart card displays (Fig. 1). We report on Reflex displays, which are inherently low power consumption, flexible, reflective, and bistable. The Reflex technology is based on the cholesteric liquid crystal displays (ChLCDs) by Kent Displays Inc.[1] The unique structure, materials, and inherent properties of Reflex displays make these displays simple to manufacture when compared with competing technologies, even for higher resolution displays.
Purpose. Despite a high prevalence of psychological distress and poor mental health in the Austra... more Purpose. Despite a high prevalence of psychological distress and poor mental health in the Australian community, use of counseling services is very low. There has been only limited research examining the profile of those who do access counseling services, mainly in terms of demographic and health behavior variables. To extend our understanding of those who currently access counseling services, this study aimed to examine the broader pattern of health service utilization by women who consulted counselors, psychologists, or social workers in the past year compared with those who did not among a population-based sample of middle-aged Australian women, and to determine whether health service utilization was independently associated with use of counseling services, controlling for other known predictors. Methods. The cross-sectional population-based mail survey data for this study came from the third survey of the mid-aged cohort of the Australian Longitudinal Study on Women's Health, conducted in 2001. The sample comprised 11,201 women aged 50-55. The main study variable was a question asking whether they had consulted a counselor/psychologist/social worker in the past year. Findings. Only 6.9% of women had consulted a counselor/psychologist/social worker in the past year. After controlling for self-reported mental health status, health behaviors and demographic variables in multivariate analysis, consulting a counselor/psychologist/social worker in the past year was significantly and positively associated with consultations with general practitioners (5 consultations; odds ratio [OR], 4.14; 95% confidence interval [CI], 2.35-7.27; p , .0001), specialist (3 consultations; OR, 2.09; 95% CI, 1.66-2.63; p , .0001), and hospital doctor (OR, 1.35; 95% CI, 1.10-1.66; p ¼ .004). Use of counseling services was not associated with use of other allied and complementary health services in multivariate analyses. Conclusions. Further research is needed to determine whether the strong independent link between self-reported use of counseling and other medical and health services among middle-aged women is best explained by general practice referral patterns, availability of services, economic factors, or different help-seeking patterns among women.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2009
14 and 16 membered Schiff base macrocyclic ligands, 7,14-dimethyl-5,12-di(N-amino)-2-methylphenyl... more 14 and 16 membered Schiff base macrocyclic ligands, 7,14-dimethyl-5,12-di(N-amino)-2-methylphenyl-1,4,8,11-tetraaza-cyclotetradecane-4,7,11,14-tetraene (L(1)) and 8,16-dimethyl-6,14-di(N-amino)-2-methylphenyl-1,5,9,13-tetraaza-cyclohexadecane-5,8,13,16-tetraene (L(2)) were synthesized by condensation reaction between 2'-methyleacetoacetanilide and aliphatic diamines. The metal complexes of the types, [ML(1)](NO(3))(2) and [ML(2)(NO(3))(2)] [M = Co(II), Ni(II), Cu(II) and Zn(II)] were prepared by interaction of ligands, L(1) or L(2) with hydrated metal(II) nitrates. The ligands and their complexes were characterized by elemental analysis, IR, (1)H and (13)C NMR, EPR, UV-Vis spectroscopy, magnetic susceptibility, conductivity measurements and ESI-mass spectral studies. The results of elemental analyses, ESI-mass and conductivity measurements confirmed the stoichiometry of ligands and their complexes while the characteristic absorption bands and resonance peaks in IR and NMR spectra confirmed the formation of ligand frameworks around the metal ions. The square planar geometry for complexes derived from ligand L(1) and octahedral environment for complexes derived from ligand L(2) with distortion in Cu(II) complex have been confirmed on the basis of results of electronic and electron spin resonance spectral studies and magnetic moment measurements. Absorption and fluorescence spectral studies revealed different binding mode for complex, [CuL(1)](NO(3))(2) as compared with [CuL(2)(NO(3))(2)] on interaction with calf thymus DNA.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2011
Synthesis and spectroscopic studies on the Schiff base ligand derived from condensation of 2-fura... more Synthesis and spectroscopic studies on the Schiff base ligand derived from condensation of 2-furaldehyde and 3,3-diaminobenzidene, L and its complexes with Co(II), Ni(II), Cu(II) and Zn(II): Comparative DNA binding studies of L and its Cu(II) and Zn(II) complexes
Children with neurofibromatosis type 1 (NF1) undergo costly surveillance scanning for a variety o... more Children with neurofibromatosis type 1 (NF1) undergo costly surveillance scanning for a variety of asymptomatic central nervous system lesions whose natural history is poorly understood. We performed a 20-year retrospective chart review of 25 patients with clinically proven NF1 who required surgery (group A) and contrasted this cohort with 150 NF1 patients who did not require surgery (group B). In group A, 52% of patients underwent multiple procedures for more than one lesion (p = 0.043). Group A patients were further distinguished from those in group B by exhibiting a greater number of optic gliomas (p = 0.015), nonoptic intracranial tumors (p = 0.006), cranial nerve (p = 0.000), paraspinal (p = 0.0062), craniofacial (p = 0.001) and visceral (p = 0.03) neurofibromas and moyamoya disease (p = 0.00), as well as a higher frequency of seizure disorder, sphenoid wing dysplasia and poor academic performance. Gadolinium enhancement occurred in 43% of optic gliomas, 50% of parenchymal glio...
Multidrug resistant-bacteria are a serious threat to the existing antibiotic armory and are aided... more Multidrug resistant-bacteria are a serious threat to the existing antibiotic armory and are aided by mobile genetic elements in their 'battle'. 1 Urinary tract infection (UTi) is an extremely common condition requiring antimicrobial therapy. 2 increasing antimicrobial resistance among bacteria causing UTi is therefore of great concern. Genetic elements that have been an increasing focus of study in the context of UTis are the 'integrons'. These elements are considered to be extremely common in UTis. 3 in particular, integrons belonging to classes 1, 2, and 3 are most commonly associated with the spread of antibiotic resistance among pathogens. 4 The class 1 integrons that carry drug resistance genes in clinical isolates have a relatively conserved structure. This structure commonly comprises two conserved DnA sequences-the 5'-Cs and 3'-Cs-separating a variable region where mobile gene cassettes are located. 5 This arrangement (5'-Cs-variable region-3'-Cs) has been used as a PCR tool for the simple recovery of cassette arrays irrespective of knowledge of the many and varied cassettes that may be present. 6 Extended spectrum b-lactamases (EsBLs) are the bacterial enzymes that impart resistance against advanced-generationcephalosporins. CTx-Ms have become the most prevalent EsBLs worldwide. 7 CTx-M type EsBLs are mainly found in Escherichia coli strains and CTx-M producers are extremely common in UTis. 8 The CTx-M-15 enzyme in particular is increasingly being reported among E. coli isolates from northern india. 9 in a study from netherlands 19% of E. coli had class 1 integron. 10 However, there is a paucity of data concerning integrons from community-acquired infections. Furthermore, no such data have been reported from india although prevalence of co-trimoxazole resistance is high among E. coli in our region. Accordingly, the objectives of our study were 1) to determine the prevalence of class 1 integrons among EsBL-producing M. AKRAM-s. sHAKiL-A
... DOI: 10.1080/14733140801889097 Margot J. Schofield a b c * & Asaduzzaman Khan d p... more ... DOI: 10.1080/14733140801889097 Margot J. Schofield a b c * & Asaduzzaman Khan d pages 12-20. Available online: 18 Feb 2008. ...
Objective: To investigate whether using a parametric statistic in comparing groups leads to diffe... more Objective: To investigate whether using a parametric statistic in comparing groups leads to different conclusions when using summative scores from rating scales compared with using their corresponding Rasch-based measures. Methods: A Monte Carlo simulation study was designed to examine between-group differences in the change scores derived from summative scores from rating scales, and those derived from their corresponding Rasch-based measures, using 1-way analysis of variance. The degree of inconsistency between the 2 scoring approaches (i.e. summative and Rasch-based) was examined, using varying sample sizes, scale difficulties and person ability conditions. Results: This simulation study revealed scaling artefacts that could arise from using summative scores rather than Rasch-based measures for determining the changes between groups. The group differences in the change scores were statistically significant for summative scores under all test conditions and sample size scenarios. ...
Journal of the Society for Information Display, 2008
This paper demonstrates the first substrate-free cholesteric liquid-crystal displays. The encapsu... more This paper demonstrates the first substrate-free cholesteric liquid-crystal displays. The encapsulated cholesteric displays are ultra-thin (with a total thickness around 20 µm) and ultra-lightweight (0.002 g/cm 2). The displays exhibit unprecedented conformability, flexibility, and drapability while maintaining electro-optical performance and mechanical integrity. All functional display layers are sequentially coated on a preparation substrate and then lifted-off from the preparation substrate to form a free-standing display. The display fabrication process, electro-optical performance, and display flexibility are discussed.
We present a flexible touch‐sensitive writing tablet utilizing a reflective bistable cholesteric ... more We present a flexible touch‐sensitive writing tablet utilizing a reflective bistable cholesteric liquid crystal laminated between two conductive‐polymer coated polyethylene‐terephthalate substrates. The device features a selective pressure response suitable for high‐resolution ...
Bistable reflective cholesteric displays are a liquid crystal display technology developed to fil... more Bistable reflective cholesteric displays are a liquid crystal display technology developed to fill a market need for very low power displays. Their unique look, high reflectivity, bistability, and simple structure make them an ideal flat panel display choice for handheld or other ...
Journal of the Society for Information Display, 2005
Bistable reflective cholesteric liquid‐crystal displays are low‐power displays that are suitable ... more Bistable reflective cholesteric liquid‐crystal displays are low‐power displays that are suitable for a variety of applications ranging from signage to high‐resolution electronic books. Recent advancements have included higher brightness, full color, black and white from a single ...
Journal of the Society for Information Display, 2009
A novel optically addressable, flexible bistable cholesteric liquid-crystal display (ChLCD) is pr... more A novel optically addressable, flexible bistable cholesteric liquid-crystal display (ChLCD) is presented. These displays utilize azo-binaphthalene photosensitive chiral dopants that undergo photo-isomerization upon exposure to light. The isomerization results in a change in the pitch of the cholesteric liquid crystal (ChLC), which enables the creation of inherently high-resolution lightweight displays that are optically written. The displays can be photo-addressed without patterned electrodes or complex addressing schemes. Capitalizing on the dynamic pitch and the bistability of photosensitive ChLCDs, the display is switched with a single pulse at a specific single voltage to drive the region of the display with a shorter pitch to the focal-conic texture and the region of the display with a longer pitch to the planar texture. Once in the different textures, the display can hold an image indefinitely regardless of ambient lighting. As such, these displays are a natural fit for badges, shelf-labels, and point-of-sale cards. In this paper, the photosensitive properties of an encapsulated display system in comparison to an unencapsulated display system is discussed. Properties such a photosensitivity, thermal relaxation, and electro-optical response are studied and reported. In addition, a flexible optically addressable ChLCD is developed and demonstrated.
Flexible, reflective, bistable displays have become the focus of significant research over the pa... more Flexible, reflective, bistable displays have become the focus of significant research over the past decade due to their appeal for alternative applications requiring low power, small form factor, and flexibility. Some of the first flexible displays to be offered in the market are non-traditional Reflex TM displays in unique and exciting new applications, such as, writing tablets, electronic skins, and smart card displays (Fig. 1). We report on Reflex displays, which are inherently low power consumption, flexible, reflective, and bistable. The Reflex technology is based on the cholesteric liquid crystal displays (ChLCDs) by Kent Displays Inc.[1] The unique structure, materials, and inherent properties of Reflex displays make these displays simple to manufacture when compared with competing technologies, even for higher resolution displays.
Purpose. Despite a high prevalence of psychological distress and poor mental health in the Austra... more Purpose. Despite a high prevalence of psychological distress and poor mental health in the Australian community, use of counseling services is very low. There has been only limited research examining the profile of those who do access counseling services, mainly in terms of demographic and health behavior variables. To extend our understanding of those who currently access counseling services, this study aimed to examine the broader pattern of health service utilization by women who consulted counselors, psychologists, or social workers in the past year compared with those who did not among a population-based sample of middle-aged Australian women, and to determine whether health service utilization was independently associated with use of counseling services, controlling for other known predictors. Methods. The cross-sectional population-based mail survey data for this study came from the third survey of the mid-aged cohort of the Australian Longitudinal Study on Women's Health, conducted in 2001. The sample comprised 11,201 women aged 50-55. The main study variable was a question asking whether they had consulted a counselor/psychologist/social worker in the past year. Findings. Only 6.9% of women had consulted a counselor/psychologist/social worker in the past year. After controlling for self-reported mental health status, health behaviors and demographic variables in multivariate analysis, consulting a counselor/psychologist/social worker in the past year was significantly and positively associated with consultations with general practitioners (5 consultations; odds ratio [OR], 4.14; 95% confidence interval [CI], 2.35-7.27; p , .0001), specialist (3 consultations; OR, 2.09; 95% CI, 1.66-2.63; p , .0001), and hospital doctor (OR, 1.35; 95% CI, 1.10-1.66; p ¼ .004). Use of counseling services was not associated with use of other allied and complementary health services in multivariate analyses. Conclusions. Further research is needed to determine whether the strong independent link between self-reported use of counseling and other medical and health services among middle-aged women is best explained by general practice referral patterns, availability of services, economic factors, or different help-seeking patterns among women.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2009
14 and 16 membered Schiff base macrocyclic ligands, 7,14-dimethyl-5,12-di(N-amino)-2-methylphenyl... more 14 and 16 membered Schiff base macrocyclic ligands, 7,14-dimethyl-5,12-di(N-amino)-2-methylphenyl-1,4,8,11-tetraaza-cyclotetradecane-4,7,11,14-tetraene (L(1)) and 8,16-dimethyl-6,14-di(N-amino)-2-methylphenyl-1,5,9,13-tetraaza-cyclohexadecane-5,8,13,16-tetraene (L(2)) were synthesized by condensation reaction between 2'-methyleacetoacetanilide and aliphatic diamines. The metal complexes of the types, [ML(1)](NO(3))(2) and [ML(2)(NO(3))(2)] [M = Co(II), Ni(II), Cu(II) and Zn(II)] were prepared by interaction of ligands, L(1) or L(2) with hydrated metal(II) nitrates. The ligands and their complexes were characterized by elemental analysis, IR, (1)H and (13)C NMR, EPR, UV-Vis spectroscopy, magnetic susceptibility, conductivity measurements and ESI-mass spectral studies. The results of elemental analyses, ESI-mass and conductivity measurements confirmed the stoichiometry of ligands and their complexes while the characteristic absorption bands and resonance peaks in IR and NMR spectra confirmed the formation of ligand frameworks around the metal ions. The square planar geometry for complexes derived from ligand L(1) and octahedral environment for complexes derived from ligand L(2) with distortion in Cu(II) complex have been confirmed on the basis of results of electronic and electron spin resonance spectral studies and magnetic moment measurements. Absorption and fluorescence spectral studies revealed different binding mode for complex, [CuL(1)](NO(3))(2) as compared with [CuL(2)(NO(3))(2)] on interaction with calf thymus DNA.
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2011
Synthesis and spectroscopic studies on the Schiff base ligand derived from condensation of 2-fura... more Synthesis and spectroscopic studies on the Schiff base ligand derived from condensation of 2-furaldehyde and 3,3-diaminobenzidene, L and its complexes with Co(II), Ni(II), Cu(II) and Zn(II): Comparative DNA binding studies of L and its Cu(II) and Zn(II) complexes
Children with neurofibromatosis type 1 (NF1) undergo costly surveillance scanning for a variety o... more Children with neurofibromatosis type 1 (NF1) undergo costly surveillance scanning for a variety of asymptomatic central nervous system lesions whose natural history is poorly understood. We performed a 20-year retrospective chart review of 25 patients with clinically proven NF1 who required surgery (group A) and contrasted this cohort with 150 NF1 patients who did not require surgery (group B). In group A, 52% of patients underwent multiple procedures for more than one lesion (p = 0.043). Group A patients were further distinguished from those in group B by exhibiting a greater number of optic gliomas (p = 0.015), nonoptic intracranial tumors (p = 0.006), cranial nerve (p = 0.000), paraspinal (p = 0.0062), craniofacial (p = 0.001) and visceral (p = 0.03) neurofibromas and moyamoya disease (p = 0.00), as well as a higher frequency of seizure disorder, sphenoid wing dysplasia and poor academic performance. Gadolinium enhancement occurred in 43% of optic gliomas, 50% of parenchymal glio...
Multidrug resistant-bacteria are a serious threat to the existing antibiotic armory and are aided... more Multidrug resistant-bacteria are a serious threat to the existing antibiotic armory and are aided by mobile genetic elements in their 'battle'. 1 Urinary tract infection (UTi) is an extremely common condition requiring antimicrobial therapy. 2 increasing antimicrobial resistance among bacteria causing UTi is therefore of great concern. Genetic elements that have been an increasing focus of study in the context of UTis are the 'integrons'. These elements are considered to be extremely common in UTis. 3 in particular, integrons belonging to classes 1, 2, and 3 are most commonly associated with the spread of antibiotic resistance among pathogens. 4 The class 1 integrons that carry drug resistance genes in clinical isolates have a relatively conserved structure. This structure commonly comprises two conserved DnA sequences-the 5'-Cs and 3'-Cs-separating a variable region where mobile gene cassettes are located. 5 This arrangement (5'-Cs-variable region-3'-Cs) has been used as a PCR tool for the simple recovery of cassette arrays irrespective of knowledge of the many and varied cassettes that may be present. 6 Extended spectrum b-lactamases (EsBLs) are the bacterial enzymes that impart resistance against advanced-generationcephalosporins. CTx-Ms have become the most prevalent EsBLs worldwide. 7 CTx-M type EsBLs are mainly found in Escherichia coli strains and CTx-M producers are extremely common in UTis. 8 The CTx-M-15 enzyme in particular is increasingly being reported among E. coli isolates from northern india. 9 in a study from netherlands 19% of E. coli had class 1 integron. 10 However, there is a paucity of data concerning integrons from community-acquired infections. Furthermore, no such data have been reported from india although prevalence of co-trimoxazole resistance is high among E. coli in our region. Accordingly, the objectives of our study were 1) to determine the prevalence of class 1 integrons among EsBL-producing M. AKRAM-s. sHAKiL-A
... DOI: 10.1080/14733140801889097 Margot J. Schofield a b c * & Asaduzzaman Khan d p... more ... DOI: 10.1080/14733140801889097 Margot J. Schofield a b c * & Asaduzzaman Khan d pages 12-20. Available online: 18 Feb 2008. ...
Objective: To investigate whether using a parametric statistic in comparing groups leads to diffe... more Objective: To investigate whether using a parametric statistic in comparing groups leads to different conclusions when using summative scores from rating scales compared with using their corresponding Rasch-based measures. Methods: A Monte Carlo simulation study was designed to examine between-group differences in the change scores derived from summative scores from rating scales, and those derived from their corresponding Rasch-based measures, using 1-way analysis of variance. The degree of inconsistency between the 2 scoring approaches (i.e. summative and Rasch-based) was examined, using varying sample sizes, scale difficulties and person ability conditions. Results: This simulation study revealed scaling artefacts that could arise from using summative scores rather than Rasch-based measures for determining the changes between groups. The group differences in the change scores were statistically significant for summative scores under all test conditions and sample size scenarios. ...
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