Hofstadter butterflies in magnetically modulated graphene bilayer: an algebraic approach

It has been shown that Bernal stacked bilayer graphene (BLG) in a uniform magnetic field demonstrates integer quantum Hall effect with a zero Landau-level anomaly \cite{Geimbilayer}. In this article we consider such system in a two dimensional periodic magnetic modulation with square lattice symmetry. It is shown algebraically that the resulting Hofstadter spectrum can be expressed in terms of the corresponding spectrum of monolayer graphene in a similar magnetic modulation. In the weak-field limit, using the tight-binding model, we also derive the Harper-Hofstadter equation for such BLG system in a periodic magnetic modulation. We further demonstrate the topological quantisation of Hall conductivity in such system and point out that the quantised Hall plateaus are equally spaced for all quantum numbers for the quantised Hall conductivity.Comment: Accepted for Publication in Physica E (Low dimensional systems and Nanostructures

An unusual presentation of Rubinstein-Taybi Syndrome with bilateral postaxial polydactyly

Rubinstein-Taybi Syndrome (RSTS) is a rare multiple congenital anomaly syndrome. Only 250 cases have been described in medical literature. We hereby present a 10-month-old male child with characteristic facial features and hand and feet anomalies. The characteristic features of hands and feet typically described are broad thumbs and halluces and clinodactyly of the 5th finger, whereas polydactyly is a rarely reported feature in this syndrome. This case promotes awareness regarding this syndrome and emphasises rarely reported features that should raise high degree of suspicion in a child presenting with multiple congenital anomalies and have a great importance in diagnosis of a genetic syndrome like RSTS. Early detection is essential for prevention of morbidity, mortality and disability

Comparison of Corneal Endothelial Cell Loss during Manual Small-incision Cataract Surgery using Visco-expression versus Irrigating Wire Vectis-assisted Nucleus Removal: A Prospective Randomised Study

Introduction: Age-related cataract is the leading cause of curable blindness in India, and Manual Small-Incision Cataract Surgery (MSICS) is a machine-independent and cost-effective alternative to phacoemulsification for handling this significant burden. In every cataract surgery, some endothelial cell loss is inevitable. Therefore, the present study was conducted to compare endothelial cell loss in the two most commonly practiced methods of nucleus delivery in MSICS. Aim: To compare and analyse endothelial cell loss during MSICS using viscoelastic/viscoexpression-assisted nucleus removal versus irrigating wire vectis-assisted nucleus removal. Materials and Methods: A prospective randomised interventional study was conducted at the Regional Institute of Ophthalmology, Postgraduate Institute of Medical Sciences (PGIMS) Rohtak, Haryana, India. The study duration was three years, from May 2018 to May 2021. A total of 250 patients with uncomplicated senile cataract over 40 years of age, with nuclear sclerosis of grade 2 or higher and “with the rule” astigmatism, were included in the study. The patients were randomly divided into Group A and Group B (125 each), who underwent MSICS using visco-expression (Group A) versus irrigating wire vectis-assisted (Group B) nucleus removal. Visual Acuity (VA), keratometry, astigmatism, pachymetry, and Endothelial Cell Density (ECD) were recorded in every patient preoperatively and postoperatively on day 1 and day 40. The Shapiro-wilk test was used to assess the normality of the data, and student’s t-test was performed to identify significant differences in continuous factors between the two groups. Chi-square test was used to find the association between factors and techniques, with a p-value <0.05 considered statistically significant. Results: The mean age of the patients was 68.5±9.4 years (range 52-89 years) with a significant male preponderance. The mean LogMAR visual acuity on Postoperative Day (POD)-1 was 0.3±0.1 for Group A, while for Group B, it was 0.5±0.2, showing a statistically significant difference (p=0.004). However, on day 40, visual acuity was comparable in both groups, with Group A (0.1±0.2) and Group B (0.1±0.1), and no significant difference (p=0.09). On POD-1, the percentage change in Endothelial Cell Density (ECD) was 4.2% in Group A and 10.6% in Group B, with a statistically significant difference (p=0.0017). On day 40, it was 2.1% and 4.8% in Group A and Group B, respectively, also showing a statistically significant difference (p=0.003). On postoperative day 40, the mean Surgically Induced Astigmatism (SIA) in Group A and Group B was 0.67±0.24 and 0.74±0.41, respectively, but this difference was statistically insignificant (p=0.074). Intra and postoperative complications such as hyphema, iridodialysis, and corneal oedema were more common in Group B than Group A. Conclusion: The study concludes that there was a statistically significant endothelial cell loss in the irrigating wire vectisassisted nucleus delivery method compared to the viscoexpression of the nucleus during MSICS. The present method also showed delayed visual rehabilitation and a higher risk of intra and postoperative complications. Therefore, viscoexpression of the nucleus should be the preferred method of nucleus delivery in every MSICS where feasible

Women personal care products and rural market penetration: Rural health marketing implications

The market penetration of female-hygiene-products Indian rural women market is one of the lowest in the world. The National Family Health Survey 2015-16 report shows that the usage of feminine hygiene products among Indian women is 48.5% in rural India and 77.5% in urban India. In their 2016 survey conducted on adolescent girls in the rural parts of Bihar and Jharkhand, Nielson found that though 46% of the respondents had heard about feminine hygiene products, only 28% were using them regularly. Evidence suggests that there is a lack of resources, education, and awareness about personal hygiene in rural areas of the country, as well as personal inhibitions and social taboos associated with the purchase and use of hygiene products on the market. Hence, the need for the study was felt to understand the consumer behaviour of rural women towards feminine hygiene products. The independent variables measuring the behaviour are consumer awareness, attitude, and social influence, and the dependent variable is purchase intentions.&nbsp

Recent trends: Medical management of infectious keratitis

This review article highlights the newer diagnostic modalities and approaches in the medical management of infectious keratitis. A Medline literature search conducted to March 2014 has been included. Recent studies or publications were selected from international indexed journals using suitable key words. Development of specular microscopy and polymerase chain reaction (PCR) has a promising role as diagnostic modalities in infectious keratitis, especially in refractory cases. Previously fortified antibiotics have been the mainstay of treatment for bacterial keratitis. Recently, the advent of fourth-generation fluoroquinolones monotherapy has shown promising results in the management of bacterial keratitis. Corneal collagen cross-linking is being considered in the refractory cases. Topical natamycin and amphotericin B should be considered as the first choice anti-fungal agents in suspected filamentous or yeast infection respectively. Voriconazole and newer routes of administration such as intrastromal and intracameral injection of conventional anti-fungal agents have demonstrated a positive clinical response. Ganciclovir is a newer anti-viral agent with promising results in herpes simplex keratitis. Thus, introduction of newer diagnostic modalities and collagen cross-linking along with fourth-generation fluoroquinolones and newer azoles have a promising role in the management of infectious keratitis

Women Personal Care Products and Rural Market Penetration: Rural Health Marketing Implications

The market penetration of female-hygiene-products Indian rural women market is one of the lowest in the world. The National Family Health Survey 2015-16 report shows that the usage of feminine hygiene products among Indian women is 48.5% in rural India and 77.5% in urban India. In their 2016 survey conducted on adolescent girls in the rural parts of Bihar and Jharkhand, Nielson found that though 46% of the respondents had heard about feminine hygiene products, only 28% were using them regularly. Evidence suggests that there is a lack of resources, education, and awareness about personal hygiene in rural areas of the country, as well as personal inhibitions and social taboos associated with the purchase and use of hygiene products on the market. Hence, the need for the study was felt to understand the consumer behaviour of rural women towards feminine hygiene products. The independent variables measuring the behaviour are consumer awareness, attitude, and social influence, and the dependent variable is purchase intentions.&nbsp

Molecular docking of triterpenoids from Neem with the ecdysone receptor of lepidopteran pests

237-248An in silico docking study was performed to evaluate the interaction of various triterpenoids present in neem with the ecdysone receptor of two economically important lepidopteran pests viz., Helicoverpa armigera (HaEcR) and Plutella xylostella (PxEcR). Twenty triterpenoids were selected for the study, and their docking scores with HaEcR and PxEcR were calculated using the program AutoDock Vina. A commercially available DAH insecticide, tebufenozide, was used as a reference ligand. Out of the twenty triterpenoids used for the study, six and nine triterpenoids recorded binding energy lower than the reference ligand, tebufenozide, when docked with HaEcR and PxEcR, respectively. Four triterpenoids, viz., isomeldenin, azdiradione, 6-deacetylnimbinene, and nimocinol, docked effectively with the ecdysone receptor of both insect pests. In addition, nimbinene and 6-deacetylnimbin also docked effectively with HaEcR and epoxyazadiradione and nimbocinol with PxEcR. Most of the lead compounds were able to form hydrogen bonds with the ecdysone receptor molecule. We found two key amino acid residues, Asn of HaEcR and Ser of PxEcR, at the 504th position, based on their ability to form hydrogen bonds with many lead triterpenoids tested. Other residues, such as Trp 526 in HaEcR and Lys 372 and Phe 520 in PxEcR, were involved in hydrophobic and π-π stacking interactions with many lead triterpenoids, suggesting these residues as an important point of interaction between receptor and ligand molecules. Triterpenoids such as tirucallol, 3-tigloylazadirachtol, and azadirone, although recorded binding energy lower than tebufenozide when docked with PxEcR, failed the prerequisite conditions laid down by Tice rule for a successful pesticide. The lower binding energy of the lead compounds suggests their stable interaction with the receptor molecule and their possible use as an ecdysone agonist or antagonist for effective insect control