Stability analysis of fractional difference equations with delay.

Long-term memory is a feature observed in systems ranging from neural networks to epidemiological models. The memory in such systems is usually modeled by the time delay. Furthermore, the nonlocal operators, such as the "fractional order difference," can also have a long-time memory. Therefore, the fractional difference equations with delay are an appropriate model in a range of systems. Even so, there are not many detailed studies available related to the stability analysis of fractional order systems with delay. In this work, we derive the stability conditions for linear fractional difference equations with an arbitrary delay τ and even for systems with distributed delay. We carry out a detailed stability analysis for the cases of single delay with τ=1 and τ=2. The results are extended to nonlinear maps. The formalism can be easily extended to multiple time delays.

Histological assessment of microtia cartilage, a potential source of autograft tissue in ear reconstruction.

Cartilage is a strong and flexible connective tissue that has many forms and functions in our body. While cartilage exhibits some forms of limited repair, for the most part, it is not particularly regenerative. Thus, in situations where patients require cartilage reconstruction, surgeons may use autografts to replace missing or damaged tissue. Cartilage tissues from different regions of the body exhibit histological differences and are in limited supply. Thus, it is important to characterize these differences to determine the most appropriate autograft source. In the case of microtia, a congenital deformity where the pinna is underdeveloped, reconstruction commonly utilizes cartilage sourced from a patient's own costal cartilage. This presents a potential morbidity risk. In this study, we evaluate the histological characteristics of microtia cartilage compared with normal auricular and costal cartilage obtained from human patients undergoing surgical resection. Histochemistry was used to evaluate cellularity, lipid content, and ECM content. Using a Bayesian statistical approach, we determined that while costal cartilage is the standard tissue donor, the microanatomy of microtia cartilage more closely reflects normal auricular cartilage than costal cartilage. Therefore, microtia cartilage may serve as an additional reservoir for cartilage during reconstruction.

Anti-spike antibody durability after SARS-CoV-2 vaccination in adolescent solid organ transplant recipients.

BACKGROUND: Adolescent solid organ transplant recipients (aSOTRs) who received three doses of the COVID-19 mRNA vaccine experience high seroconversion rates and antibody persistence for up to 3 months. Long-term antibody durability beyond this timeframe following three doses of the SARS-CoV-2 mRNA vaccine remains unknown. We describe antibody responses 6 months following the third vaccine dose (D3) of the BNT162b2 mRNA vaccination among aSOTRs. METHODS: Participants in a multi-center, observational cohort who received the third dose of the vaccine were analyzed for antibodies to the SARS-CoV-2 spike protein receptor-binding domain (Roche Elecsys anti-SARS-CoV-2-S positive: ≥0.8, maximum: >2500 U/mL). Samples were collected at 1-, 3-, and 6-months post-D3. Participants were surveyed at each timepoint and at 12-months post-D3. RESULTS: All 34 participants had positive anti-RBD antibody titers 6 months post-D3. Variations in titers occurred between 3 and 6 months post-D3, with 8/28 (29%) having decreased antibody levels at 6 months compared to 3 months and 2/28 (7%) reporting increased titers at 6 months. The remaining 18/28 (64%) had unchanged antibody titers compared to 3-month post-D3 levels. A total of 4/34 (12%) reported breakthrough infection within 6 months and 3/32 (9%) reported infection after 6-12 months following the third dose of the SARS-CoV-2 mRNA vaccine. CONCLUSIONS: The results suggest that antibody durability persists up to 6 months following three doses of the SARS-CoV-2 mRNA in aSOTRs. Demography and transplant characteristics did not differ for those who experienced antibody weaning. Breakthrough infections did occur, reflecting immune-evasive nature of novel variants such as Omicron.

Air-Abrasion in Dentistry: A Short Review of the Materials and Performance Parameters.

The selection of abrasive material and parameters of the Air-Abrasion device for a particular application is a crucial detail. However, there are no standard recommendations or manuals for choosing these details; the operator must depend on his experience and knowledge of the procedure to select the best possible material and set of parameters. This short review attempts to identify some of the effects that the selection of material and parameters could have on the performance of the Air-Abrasion procedure for a particular application. The material and parameter data are collected from various studies and categorized according to the most popular materials in use right now. These studies are then analyzed to arrive at some inferences on the performance of Air-Abrasion materials and parameters. This review arrives at a few conclusions on the effectiveness of a material and parameter set, and that there is potential for developments in the area of standardizing parameter selection; also, there is scope for further studies on Bio-Active Glass as an alternative to the materials currently used in Air-Abrasion.

The spectrum of cytological findings in patients with BCG lymphadenitis: A series of 13 cases.

CONTEXT: Bacillus Calmette-Guérin (BCG) vaccine has been used to prevent tuberculosis and/or its severe complications for long. BCG lymphadenitis is a common complication of the vaccine, which is sometimes subjected to cytological examination. The aim of the study is to describe the cytological findings of BCG lymphadenitis. SETTINGS: The study was conducted in a tertiary care hospital in the western part of India from January 2021 to December 2022. DESIGN: The study was performed on archived material of all patients who were referred to the fine needle aspiration clinic for cytology examination. Clinical and pathological data of cases were retrieved, and cases of BCG lymphadenitis were selected in the study based on these data. Slides of cases were retrieved, and cytological findings were studied. MATERIALS AND METHODS: Papanicolaou, Giemsa, and Hematoxylin & eosin-stained smears, as well as Ziehl-Neelson stain (Z.N. stain) smears of all BCG lymphadenitis cases, were retrieved. Cases were reviewed for individual cytological features and overall cytological diagnostic categories. Z.N. stain smears were evaluated for acid-fast bacilli. RESULTS AND CONCLUSIONS: Diagnostic categories observed in BCG lymphadenitis include suppurative lymphadenitis/abscess (15 %), necrotizing lymphadenitis (23 %), necrotizing granulomatous lymphadenitis (46 %), suppurative granulomatous lymphadenitis (8 %), non-necrotizing granulomatous lymphadenitis (8 %). Acid-fast bacilli were detected by Z.N. stain in 8 cases (62 %). The cytological findings of BCG lymphadenitis closely overlap with those of tuberculous lymphadenitis. So, clinical context is very important while reporting isolated axillary lymphadenopathy, specifically in recently vaccinated infants, to avoid misdiagnosis as tuberculous lymphadenitis.

Omicron Infections in Vaccinated Pediatric Solid Organ Transplant Recipients.

SARS-CoV-2 infection during the Omicron period was frequent amongst a cohort of vaccinated pediatric solid organ transplant recipients (pSOTRs) despite robust anti-receptor-binding domain (anti-RBD) antibody response, suggesting poor neutralizing capacity against Omicron subvariants. Breakthrough infections among pSOTRs were overall limited in severity.

MRI-Based Deep Learning Method for Classification of IDH Mutation Status.

Isocitrate dehydrogenase (IDH) mutation status has emerged as an important prognostic marker in gliomas. This study sought to develop deep learning networks for non-invasive IDH classification using T2w MR images while comparing their performance to a multi-contrast network. Methods: Multi-contrast brain tumor MRI and genomic data were obtained from The Cancer Imaging Archive (TCIA) and The Erasmus Glioma Database (EGD). Two separate 2D networks were developed using nnU-Net, a T2w-image-only network (T2-net) and a multi-contrast network (MC-net). Each network was separately trained using TCIA (227 subjects) or TCIA + EGD data (683 subjects combined). The networks were trained to classify IDH mutation status and implement single-label tumor segmentation simultaneously. The trained networks were tested on over 1100 held-out datasets including 360 cases from UT Southwestern Medical Center, 136 cases from New York University, 175 cases from the University of Wisconsin-Madison, 456 cases from EGD (for the TCIA-trained network), and 495 cases from the University of California, San Francisco public database. A receiver operating characteristic curve (ROC) was drawn to calculate the AUC value to determine classifier performance. Results: T2-net trained on TCIA and TCIA + EGD datasets achieved an overall accuracy of 85.4% and 87.6% with AUCs of 0.86 and 0.89, respectively. MC-net trained on TCIA and TCIA + EGD datasets achieved an overall accuracy of 91.0% and 92.8% with AUCs of 0.94 and 0.96, respectively. We developed reliable, high-performing deep learning algorithms for IDH classification using both a T2-image-only and a multi-contrast approach. The networks were tested on more than 1100 subjects from diverse databases, making this the largest study on image-based IDH classification to date.

Anti-pathogenicity of Acanthus ilicifolius leaf extracts against A. hydrophila infection in Labeo rohita fingerlings.

Antibiotic resistance has become one of the inevitable barrier in aquaculture disease management. Herbal drugs has evolved to be the novel ways of combating drug resistant pathogens. In the current investigation, leaf extracts of mangrove plant, Acanthus ilicifolius were assessed for in vitro studies, among the selected four extracts, methanol extract has expressed highest antibacterial activity against P .aeruginosa (4 ± 0.3 mm), A. hydrophila (5.9 ± 0.5 mm), S. aureus (3.5 ± 0.7 mm) and B. subtilis (2.9 ± 0.5 mm) and antioxidant activity, DPPH (81.3 ± 1.0 AAEµg/ml) and FRAP (139.1 ± 1.5 AAEµg/ml).TPC and TFC were higher in the methanolic extract and has exhibited positive correlation with both DPPH and FRAP assays. Considering the in vitro efficiency, methanol extract was purified successively by column and thin layer chromatography and characterisation by GC-MS unveiled the presence of 2-Propanethiol, Trimethylphosphine, Pentanoyl chloride, Dimethylhydroxymethylphosphine and Propanedinitrile, ethylidene. A. hydrophila infected L. rohita fingerlings has survival percentage 81% and 94% in extract treated groups over 0% in negative control and 71% in positive control.

Hot-melt extruded in situ gelling systems (MeltDrops Technology): Formulation development, in silico modelling and in vivo studies.

In situ gelling systems (ISGS) can prolong retention time and bioavailability of ophthalmic solutions. The complexity and cost of ISGS avert their industrial scale-up and clinical implementation. In this study, we demonstrate novel application of hot-melt extrusion (HME) technology for continuous manufacturing of ISGS (MeltDrops Technology). Timolol maleate (TIM) and dorzolamide hydrochloride (DRZ) loaded MeltDrops were successfully developed using HME for glaucoma management, thereby resolving issues with batch manufacturing of ISGS, prolonging retention time thus improving bioavailability. The MeltDrops technology involves one-step, i.e., passing all the ingredients through an extruder at a screw speed between 20 and 50 rpm and barrel temperature of 80 °C. The comparative evaluation of MeltDrops and batch-processed ISGS demonstrated that MeltDrops exhibited better physical and chemical content uniformity. The extrusion temperature and screw speed were critical factors influencing content uniformity and properties of the MeltDrops. MeltDrops showed sustained drug release for > 12 h in vitro (TIM = 83.07%; DRZ = 60.43%, 12 h) versus marketed eyedrops. The developed MeltDrops followed Peppas-Sahlin model, combining Fickian diffusion and swelling processes. The in vivo study in New Zealand rabbits revealed superior effectiveness and safety of the MeltDrops as compared to the marketed eyedrops. Herein we conclude, MeltDrops would serve as a cutting-edge platform technology that can be used to manufacture various ISGS with one-step processability, cost-effectiveness, and improved product quality, which are otherwise processed by batch manufacturing that involves numerous complex processing steps.

Association of Methylenetetrahydrofolate Reductase Gene Polymorphism in Mothers With Adverse Clinical Outcomes in Neonates.

BACKGROUND: The presence of polymorphic methylenetetrahydrofolate reductase (MTHFR) in mothers poses a risk for numerous detrimental outcomes in neonates. The present study investigated the association of maternal MTHFR A1298C and C677T single nucleotide polymorphisms (SNPs) with the clinical outcomes in their neonates. MATERIALS AND METHODS: The cross-sectional study included 60 mothers and their neonates. Blood samples from mothers were analyzed for MTHFR A1298C and C677T SNP genotyping by real-time polymerase chain reaction. Clinical details of mothers and neonates were documented. Study groups were stratified based on wild, heterozygous, and mutant genotypes for the respective polymorphisms observed in mothers. Multinomial regression was applied for the association, followed by gene model formulation to estimate the impact of the genetic variants on the outcomes. RESULTS: The frequency percentages of mutant CC1298 and TT677 genotypes were 25% and 8.06%, respectively, and the mutant allele frequencies (MAF) were 42.5% and 22.5%. Percentages of adverse outcomes such as intrauterine growth restriction, sepsis, anomalies, and mortality were higher in neonates born to mothers with homozygous mutant genotypes. Maternal C677T MTHFR SNPs revealed a significant association with neonatal anomalies (p = 0.001). The multiplicative risk model depicted OR (95% CI) for CT vs. CC+TT as 3.0 (95% CI: 0.66-13.7), and for TT vs. CT+CC was 15 (95% CI: 2.01-112.12). The C677T SNP in mothers predicted a dominant model for neonatal death (OR (95% CI): 5.84 (0.57-60.03), p = 0.15), whereas the A1298C reported recessive model for 1298CC mothers (OR (95% CI): 11 (1.05-115.5), p = 0.02). Both the genotypes assumed a recessive model for adverse neonatal outcomes: OR (95%CI) for CC vs. AA+AC was 3.2 (0.79-12.9, p = 0.1), and for TT vs. CC+CT was 5.48 (0.57-175.7, p = 0.2). The risk for sepsis in neonates was nearly six times higher in those born from mothers with homozygous CC1298 and TT677 than in the wild and heterozygous variants. CONCLUSION: Mothers with C677T and A1298C SNPs are highly susceptible to adverse outcomes in their neonates. Hence, screening the SNPs during the antenatal period can purposefully serve as a better predictive marker, following which proper clinical management could be planned.

Field and agroinoculation screening of national collection of urd bean (Vigna mungo) germplasm accessions for new sources of mung bean yellow mosaic virus (MYMV) resistance.

Yellow mosaic disease (YMD) is a major problem in Urd bean (Vigna mungo L.) in India, which causes huge yield losses. Breeding for wide spectrum and durable Mungbean yellow mosaic virus (MYMV) resistance and cultivating resistant cultivars is the most appropriate and effective approach. However, the task has become challenging with the report of at least two species of the virus, viz., Mungbean yellow mosaic virus (MYMV) and Mungbean yellow mosaic India virus (MYMIV) and their recombinants; the existence of various isolates of these species with varied virulence and rapid mutations noted in the virus as well as in the whitefly vector population. Thus the present study was carried out to identify and characterize novel and diverse sources of YMV resistance and develop linked molecular markers for breeding durable and broadspectrum resistant urdbean cultivars against YMV. Towards this goal, we have screened 998 accessions of urdbean national collection of germplasm against YMD Hyderabad isolate both in a field under the natural level of disease incidence and through agro inoculation in the laboratory using viruliferous clones of the same isolate. Ten highly resistant accessions identified through repeated testing have been characterized in terms of reported linked markers. We attempted to see diversity among the ten resistant accessions reported here using earlier reported resistance-linked SCAR marker YMV1 and SSR CEDG180 marker. SCAR marker YMV1 did not amplify with any of the 10 accessions. But with CEDG180, results suggested that 10 accessions shortlisted through field and laboratory tests do not carry PU31 allele and this shows that it may be likely to carry novel gene(s). Further studies are needed to genetically characterize these new sources.

Study of low-dimensional nonlinear fractional difference equations of complex order.

We study the fractional maps of complex order, α e, for 0 < α < 1 and 0 ≤ r < 1 in one and two dimensions. In two dimensions, we study Hénon, Duffing, and Lozi maps, and in 1 d, we study logistic, tent, Gauss, circle, and Bernoulli maps. The generalization in 2 d can be done in two different ways, which are not equivalent for fractional order and lead to different bifurcation diagrams. We observed that the smooth maps, such as logistic, Gauss, Duffing, and Hénon maps, do not show chaos, while discontinuous maps, such as Bernoulli and circle maps,show chaos. The tent and Lozi map are continuous but not differentiable, and they show chaos as well. In 2 d, we find that the complex fractional-order maps that show chaos also show multistability. Thus, it can be inferred that the smooth maps of complex fractional order tend to show more regular behavior than the discontinuous or non-differentiable maps.

An update on the novel approaches towards skills assessment of ophthalmology residents in the Indian scenario.

An essential part of the teaching-learning paradigm is assessment. It is one of the ways to achieve feedback for the various methods that have been used to impart a particular skill. This is true of ophthalmology training, where various clinical and surgical skills are learned as part of the residency program. In preparation for residents to become proficient ophthalmologists, both formative and summative assessments are of paramount importance. At present, assessment is primarily summative in the form of a university examination, including theory and practical examinations that are conducted at the end of the three years of residency. A formative assessment can make course corrections early on, allowing for an improved understanding of the subject and the acquisition of clinical and surgical skills. Formative assessments also allow us to customize the teaching methodology considering individual residents' learning capabilities. In addition, formative assessments have the advantage of alleviating the stress of a "final" examination, which could sometimes result in a less-than-optimum performance by the residents. The COVID-19 pandemic has forced us to adopt new teaching methods, which has led to the adoption of changes in assessment. In this regard, we discuss the different assessment tools available, their pros and cons, and how best these tools can be made applicable in the setting of an ophthalmology residency program.

Silencing acetyl-CoA carboxylase A and sterol regulatory element-binding protein 1 genes through RNAi reduce serum and egg cholesterol in chicken.

Cholesterol is synthesized in chicken through de novo lipid biosynthetic pathway where two most important genes viz. SREBP1 and ACACA play immense role. To minimize cholesterol synthesis, RNAi approach was adopted and accordingly, we developed transgenic chicken possessing ACACA and SREBP1 shRNA constructs, which showed lower level of ACACA and SREBP1 in serum. The serum total cholesterol, triglycerides, HDL and LDL cholesterol was significantly lower by 23.8, 35.6, 26.6 and 20.9%, respectively in SREBP1 transgenic birds compared to the control. The egg total cholesterol and LDL cholesterol content was numerically lower in both ACACA and SREBP1 transgenic birds by 14.3 and 13.2%, and 10.4 and 13.7%, respectively compared to the control. It is concluded that the protocol was perfected to develop transgenic chicken through RNAi for knocking down the expression of ACACA and SREBP1 proteins, which minimized the cholesterol and triglycerides contents in serum and eggs.

Nebulizer systems: a new frontier for therapeutics and targeted delivery.

Drug delivery via the pulmonary route is a cornerstone in the pharmaceutical sector as an alternative to oral and parenteral administration. Nebulizer inhalation treatment offers multiple drug administration, easily employed with tidal breathing, suitable for children and elderly, can be adapted for severe patients and visible spray ensures patient satisfaction. This review discusses the operational and mechanical characteristics of nebulizer delivery devices in terms of aerosol production processes, their usage, benefits and drawbacks that are currently shaping the contemporary landscape of inhaled drug delivery. With the advent of particle engineering, novel inhaled nanosystems can be successfully developed to increase lung deposition and decrease pulmonary clearance. The above-mentioned advances might pave the path for treating a life-threatening disorder like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which is also discussed in the current state of the art.

Collateral damage: Corneal injury due to mask use during the COVID-19 pandemic - A case series.

Though masks are the best shield against COVID-19, they can be a source of discomfort and ocular side effects. We discuss three cases of corneal injury due to mask use. Three patients, who were healthcare workers, presented with discomfort, photophobia, and pain in the eyes. While adjusting the mask, they had an ocular injury. There were multiple superficial linear abrasions in the eyes. They recovered with treatment. Though masks are imperative during the COVID-19 pandemic, it is important to be aware of a possible mask injury.

Comparative Evaluation of the Effectiveness of Different Pain-alleviating Methods before Local Anesthetic Administration in Children of 6 to 12 Years of Age: A Clinical Study.

BACKGROUND AND AIM OF THE STUDY: Pediatric patients are apprehensive regarding having dental treatment mainly because of painful local anesthetic (LA) injections. Various techniques like transcutaneous electrical nerve stimulation (TENS), topical anesthetic agents, and vibrator device are introduced to reduce discomfort before LA administration. Therefore, the present study aimed to compare and evaluate the effectiveness of TENS, 2% lignocaine gel, eutectic mixture of lignocaine and prilocaine (EMLA), and vibrating device before LA injections in alleviating pain in pediatric patients. MATERIALS AND METHODS: Sixty healthy children aged 6 to 12 years who required LA injections for dental procedures were selected and divided into four groups with 15 patients in each group. Wong-Baker's facial pain rating scale (WBFPRS) and face, legs, activity, cry, and consolability scale (FLACC) are used for pain perception which are tabulated, and statistically analyzed. RESULTS: The test results demonstrated that the TENS group has shown the least mean WBFPRS and FLACC score, followed by vibrator devices, EMLA gel, and lignocaine gel. CONCLUSION: The newly introduced TENS apparatus showed encouraging results, hence can be used as a safe and reliable technique to be used in pediatric dentistry. HOW TO CITE THIS ARTICLE: Patil SB, Popali DD, Bondarde PA, et al. Comparative Evaluation of the Effectiveness of Different Pain-alleviating Methods before Local Anesthetic Administration in Children of 6 to 12 Years of Age: A Clinical Study. Int J Clin Pediatr Dent 2021;14(4):447-453.

Purification and characterization of bioactive compounds extracted from Suaeda maritima leaf and its impact on pathogenicity of Pseudomonas aeruginosa in Catla catla fingerlings.

Incidence of various dreadful microbial infections and the development of antibiotic resistance by infection causative microbes are the main reasons for reducing aquaculture productivity. Hence, there is an immense need for the discovery of alternative and efficient treatment for quick recovery of diseased fishes. In the present study, Suaeda maritima leaf extracts (hexane, diethyl ether, ethanol, and water) were screened for in vitro and in vivo antibacterial and antioxidant activities. Out of all the four extracts, ethanolic extract showed highest antibacterial activity against S. aureus (4.9 ± 1.3 mm), B. subtilis (1.6 ± 0.3 mm), K. pneumoniae (4.2 ± 1.8 mm), and P. aeruginosa (4.1 ± 1.2 mm). Similarly, antioxidant activity was also higher for ethanolic extract (500 µg/mL) based on DPPH radical scavenging ability (71.6 ± 1.4%) and reducing potential (149 µg/mL) assays. Further, ethanolic extract was purified consecutively via column chromatography and preparative TLC where an active fraction was selected based on highest antibacterial (10.1 ± 1.4 mm) and antioxidant properties (82.3 ± 2.8%). Active fraction was loaded onto mass spectroscopy and identified the presence of four active constituents such as 1,2,9,10-tetramethoxy-6-methyl-5,6,6a,7-tetrahydro-4H-dibenzo[de,g]quinolin-3-yl) methanol; 3',7-Dimethoxy-3-hydroxyflavone; Saponin and (19R)9acetyl19hydroxy10,14dimethyl20oxopentacyclo[11.8.0.0 < 2,10 > .0 < 4,9 > .0 < 14,19 >]henicos-17-yl-acetate. Besides, in vivo studies were conducted on Catla catla fingerlings infected with P. aeruginosa under laboratory conditions. The fingerlings were segregated into 5 groups, among which group 4 and 5 were treated with crude and purified extracts. Both the extracts were efficient in treating infected fingerlings and recorded 100% survival rate which is even better than group-3 treated with a synthetic antibiotic (77%). Hence, S. maritima leaf extract can be considered as a possible alternative medicine in aquaculture.

Protocol for tissue clearing and 3D analysis of dopamine neurons in the developing mouse midbrain.

Advances in tissue clearing enable analysis of complex migratory patterns of developing neurons in whole intact tissue. Here, we implemented a modified version of 3DISCO to study migration of midbrain dopamine (DA) neurons. We provide a detailed protocol starting from whole-brain immunostaining, tissue clearing, and ultramicroscopic imaging to post-acquisition quantification and analysis. This protocol enables precise quantification of DA neuron migration but can also be applied more generally for analyzing neuron migration throughout the nervous system. For complete details on the use and execution of this protocol, please refer to Brignani et al. (2020).