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Hereby, in this paper, we have reported synthesis of uniform spherical-shaped nanoparticles of zinc oxide via green method, as well as their photocatalytic activity. The nanoparticles of zinc oxide were synthesized utilizing flower extract of Rhododendron arboreum where it performs the function of reducing as well as capping agent. The synthesized nanoparticles were characterized by numerous spectroscopic techniques such as UV–Vis and FT-IR. Scanning electron microscope analysis of product revealed spherical zinc oxide nanoparticles. Energy-dispersive spectral analysis indicated elemental composition, i.e., oxygen and zinc. The green synthesized zinc oxide nanoparticles have been employed as nanocatalyst for photocatalytic degradation of two cationic dyes, i.e., Fuchsin basic and Malachite green dye. In addition, various physicochemical parameters such as effect of the dye concentration, catalyst dosage and pH have also been optimized indicating better performance of these nanoparticles. Zinc oxide nanoparticles showed 99.18% degradation of Malachite green dye and 99.272% degradation of Fuchsin basic dye. These nanoparticles have great potential candidate as developing catalyst for selective degradation of cationic dyes. [ABSTRACT FROM AUTHOR]

The public health policy depends on the management, quality, and coverage aspects. However, the assessment analysis of spatial patterns and distribution of public health services is still a challenge. This paper attempts to analyze the availability and accessibility of public health facilities in the Muktsar district of Punjab at the village level. Spatial and attribute data for public health facilities have been used within the GIS platform to produce accurate measures of accessibility. The average nearest neighbor tool has been used for spatial patterns of services in the district. Near analysis tool has been used to calculate distances from demand points (populations) to providers (facilities). Apart from these, the ratios of public health facilities to population were calculated for the identification of underserved and over-served areas. The study advocates that the spatial pattern of public health facilities is significantly clustered (p value 0.000) with a Z-score of − 5.18. It has been found that urban areas of the Muktsar district were identified as having a higher density of health facilities, whereas villages located in the marginal parts have the lowest density of health facilities. When looking at the average distance from village centroids to health facilities, it varies considerably from village to village. Considerably less than 60 percent of the population living in 108 villages has access to public health facilities. Apart from these, 40 percent of the population living in 126 villages has the greatest increase in the distance while accessing these facilities. [ABSTRACT FROM AUTHOR]

Urine infections are one of the most prevalent concerns for the healthcare industry that may impair the functioning of the kidney and other renal organs. As a result, early diagnosis and treatment of such infections are essential to avert any future complications. Conspicuously, in the current work, an intelligent system for the early prediction of urine infections has been presented. The proposed framework uses IoT-based sensors for data collection, followed by data encoding and infectious risk factor computation using the XGBoost algorithm over the fog computing platform. Finally, the analysis results along with the health-related information of users are stored in the cloud repository for future analysis. For performance validation, extensive experiments have been carried out, and results are calculated based on real-time patient data. The statistical findings of accuracy (91.45%), specificity (95.96%), sensitivity (84.79%), precision (95.49%), and f-score(90.12%) reveal the significantly improved performance of the proposed strategy over other baseline techniques. [ABSTRACT FROM AUTHOR]

The mechanistic pathways for nucleophilic aromatic substitution of the nitro groups of 5,7-dinitro-3H-quinazolin-4-one and 1,3-dinitro-10H-dibenzo[b,f][1,4]oxazepin-11-one with 1H-1,2,3-triazole have been studied in both gas and solvent phase employing DFT/B3LYP calculations using 6-31G(d,p) basis set. The energetic parameters, i.e., free energy profiles along the reaction route and H-bond energy, charge analysis, and structural parameters have supported mechanistic pathway involving one-step concerted mechanism via formation of transition state during the reaction course. Despite substantial steric hindrance at adjacent position to fusion point, the regioselective attack of 1H-1,2,3-triazole has been observed at peri-position of benzannulated heterocycles. This regioselectivity is credited to intramolecular hydrogen bond C–H···O = C which stabilizes peri-transition state formation rather than para-transition state. The hydrogen bond acceptor–donor interactions have been studied using AIM method. The DFT and AIM analysis-derived results are compared for different sized dinitro-substituted benzannulated heterocycles and these studies have confirmed the contribution of substantial steric hindrance at peri-position with increased size of heterocycle. As benzannulated heterocycles are quite significant from the perspective of medicinal and natural product chemistry, this work will fulfill the need to find an efficient synthetic method for benzannulated heterocycles. [ABSTRACT FROM AUTHOR]

In recent years, Healthcare 4.0, the fourth healthcare revolution, has piqued the interest of numerous researchers around the world. Healthcare 4.0 is a relatively new term that has evolved from Industry 4.0 to meet diverse requirements in the healthcare domain. Healthcare 4.0 serves as a technological catalyst for accelerated growth by integrating cutting-edge industrial technologies. Despite the evolving nature of Healthcare 4.0 research, a complete and systematic survey of recent research on it has been scarce. Conspicuously, this study intends to present a systematic survey by investigating the recent trends, key constraints, and application areas of Healthcare 4.0. Further, a comprehensive survey of the research is used to identify the essential technologies required for the effective adoption of Healthcare 4.0. The research was conducted using the PRISMA methodology and an exhaustive search of all easily accessible libraries and academic repositories was made to obtain the relevant literature. At last, a diversity of outstanding issues are also presented to assist scholars and professionals who are interested in undertaking futuristic research in the current field. [ABSTRACT FROM AUTHOR]

Viral encephalitis is a contagious disease that causes life insecurity and is considered one of the major health concerns worldwide. It causes inflammation of the brain and, if left untreated, can have persistent effects on the central nervous system. Conspicuously, this paper proposes an intelligent cyber-physical healthcare framework based on the IoT–fog–cloud collaborative network, employing soft-computing technology and information fusion. The proposed framework uses IoT-based sensors, electronic medical records, and user devices for data acquisition. The fog layer, composed of numerous nodes, processes the most specific encephalitis symptom-related data to classify possible encephalitis cases in real time to issue an alarm when a significant health emergency occurs. Furthermore, the cloud layer involves a multi-step data processing scheme for in-depth data analysis. First, data obtained across multiple data generation sources are fused to obtain a more consistent, accurate, and reliable feature set. Data preprocessing and feature selection techniques are applied to the fused data for dimensionality reduction over the cloud computing platform. An adaptive neuro-fuzzy inference system is applied in the cloud to determine the risk of a disease and classify the results into one of four categories: no risk, probable risk, low risk, and acute risk. Moreover, the alerts are generated and sent to the stakeholders based on the risk factor. Finally, the computed results are stored in the cloud database for future use. For validation purposes, various experiments are performed using real-time datasets. The analysis results performed on the fog and cloud layers show higher performance than the existing models. Future research will focus on the resource allocation in the cloud layer while considering various security aspects to improve the utility of the proposed work. [ABSTRACT FROM AUTHOR]

The recent outbreak of novel coronavirus disease (COVID-19) has resulted in healthcare crises across the globe. Moreover, the persistent and prolonged complications of post-COVID-19 or long COVID are also putting extreme pressure on hospital authorities due to the constrained healthcare resources. Out of many long-lasting post-COVID-19 complications, heart disease has been realized as the most common among COVID-19 survivors. The motivation behind this research is the limited availability of the post-COVID-19 dataset. In the current research, data related to post-COVID complications are collected by personally contacting the previously infected COVID-19 patients. The dataset is preprocessed to deal with missing values followed by oversampling to generate numerous instances, and model training. A binary classifier based on a stacking ensemble is modeled with deep neural networks for the prediction of heart diseases, post-COVID-19 infection. The proposed model is validated against other baseline techniques, such as decision trees, random forest, support vector machines, and artificial neural networks. Results show that the proposed technique outperforms other baseline techniques and achieves the highest accuracy of 93.23%. Moreover, the results of specificity (95.74%), precision (95.24%), and recall (92.05%) also prove the utility of the adopted approach in comparison to other techniques for the prediction of heart diseases. [ABSTRACT FROM AUTHOR]

With increase in the use of contactless deliveries during the times such as COVID-19 pandemic, the emphasis was to minimize the human presence to reduce the spread of virus. In this regard, drones are one promising alternative to be used as delivery agents. However, security and Quality of Service (QoS) are major concerns while making use of drones for deliveries. In order to secure the drone communication system, we propose, CovaDel: a blockchain-based scheme to secure data transactions for the drone delivery use case that works in a phased manner. The proposed scheme make use of decoupled blockchain architecture to overcome the limited resources capabilities of drones to perform blockchain-based computations. Further, to ensure the QoS adherence, we also propose a QoS-aware communication approach that handles collisions and congestion on the basis of firefly algorithm's attractiveness parameter (light intensity) received by the drones. Results obtained using a simulated environment verify the efficacy of the proposed scheme on the basis of gas consumed, transaction time, average network throughput, and delay. [ABSTRACT FROM AUTHOR]

Conflicting reports of HRT necessitates exploration of therapeutic interventions with the least side effects to preserve metabolic homeodynamics in women later in life. The current study was designed to elucidate the cumulative effects of aging and/or high fat diet (HFD) on some metabolic indicators and their management by Tinospora cordifolia stem powder (TCP) using middle-aged acyclic and young adult cyclic female rats as the model system. Animals were fed on either normal chow or HFD supplemented with or without TCP. Blood and liver tissue were collected for biochemical, and histological studies as well as for expression of proteins regulating lipid metabolism. Animals fed with TCP supplemented normal chow feed showed bodyweight management over 12-weeks despite their high feed and calories intake compared to young and age-matched controls as well as HFD-fed animals. TCP dose used was not toxic and rather prevented age-associated liver dysfunctions and ameliorated dyslipidemia and oxidative stress, normalized blood glucose, insulin, leptin, and secretary pro-inflammatory cytokines. Further, bodyweight management effect of TCP was observed to target AMPK signalling pathway as the mediator of lipogenesis, sterol biosynthesis, lipolysis, and β-oxidation of fatty acids. These findings suggest that TCP supplementation in diet may be a potential interventional strategy to ameliorate aging-associated hepatic and metabolic dysfunctions and to promote healthy aging. [ABSTRACT FROM AUTHOR]

SARS-CoV2 pandemic exposed the limitations of artificial intelligence based medical imaging systems. Earlier in the pandemic, the absence of sufficient training data prevented effective deep learning (DL) solutions for the diagnosis of COVID-19 based on X-Ray data. Here, addressing the lacunae in existing literature and algorithms with the paucity of initial training data; we describe CovBaseAI, an explainable tool using an ensemble of three DL models and an expert decision system (EDS) for COVID-Pneumonia diagnosis, trained entirely on pre-COVID-19 datasets. The performance and explainability of CovBaseAI was primarily validated on two independent datasets. Firstly, 1401 randomly selected CxR from an Indian quarantine center to assess effectiveness in excluding radiological COVID-Pneumonia requiring higher care. Second, curated dataset; 434 RT-PCR positive cases and 471 non-COVID/Normal historical scans, to assess performance in advanced medical settings. CovBaseAI had an accuracy of 87% with a negative predictive value of 98% in the quarantine-center data. However, sensitivity was 0.66–0.90 taking RT-PCR/radiologist opinion as ground truth. This work provides new insights on the usage of EDS with DL methods and the ability of algorithms to confidently predict COVID-Pneumonia while reinforcing the established learning; that benchmarking based on RT-PCR may not serve as reliable ground truth in radiological diagnosis. Such tools can pave the path for multi-modal high throughput detection of COVID-Pneumonia in screening and referral. [ABSTRACT FROM AUTHOR]

The nucleophilic aromatic substitution reactions of 4,6-dinitroisoindoline-1,3-dione with 1,2,3-triazole isomers, i.e., 1H-1,2,3-triazole and 2H-1,2,3-triazole, have been investigated theoretically using DFT/B3LYP calculations employing 6-31G(d,p) basis set in gas phase as well as in solvent phase. The computational studies have supported the formation of transition states via one-step concerted mechanism for the nucleophilic aromatic displacement of nitro groups with 1,2,3-triazoles rather than intermediate formation via two-step addition-elimination mechanism. The amination of 4,6-dinitroisoindoline-1,3-dione with 1,2,3-triazole isomers have revealed regioselectivity of peri-attack despite sterically favorable para-attack. The regioselectivity is attributed to the stabilization of the transition state through intra-molecular hydrogen bond C-H···O=C. This work presents the role of C-H bond as an effective hydrogen bond donor. The molecular interactions through hydrogen bonding have been investigated using AIM method. This work shall result in the synthesis of new regioselective 1,2,3-triazole-derived phthalimide compounds possessing potential biological candidature. [ABSTRACT FROM AUTHOR]

The purpose of this study is to study the effect of age on the correlation between heart rate variability (HRV) and blood pressure variability (BPV). To meet this end, multi-scale cross correlation (CC) analysis of HRV and systolic blood pressure variability (SBPV) was performed. The Approximate Entropy (ApEn) and Recurrence Quantification Analysis (RQA) derived indices, calculated from RR interval series (RRi) and systolic blood pressure (SBP) series at multiple temporal scales, are the basis of this CC analysis. For the computation of ApEn and RQA indices, the tolerance threshold (r) is chosen by either: (i) selecting any arbitrary value (0.2) within the recommended range (0.1–0.25) times standard deviation (SD) of time series, and (ii) taking the 'r' (ropt) corresponding to maximum ApEn (ApEnmax) as tolerance threshold. It is found that (i) at each time scale (τ), a lower SD is observed when indices are computed using ropt than r = 0.2 × SD (r0.2), for RRi as well as SBP series, (ii) descriptive indices of RRi are found significant (p < 0.05) at all scales (τ), however for SBP, these are found insignificant (p > 0.05) at most of the scales, (iii) CC values of descriptive statistics viz., mean and SD are not significant (p > 0.05) irrespective of τ, barring τ = 1, (iv) CC values of ApEn and RQA indices, found using ropt, are found significant (p < 0.05) and provide enhanced stratification at τ = 1, 2 and 3, whereas this significant correlation and strong classification is missing for indices calculated using r0.2, and (v) Lastly as τ increases, ApEn and RQA indices, computed with ropt, reverse their trend but manage to provide significant difference in elder and younger subjects. It is concluded that HRV and SBPV interactions gets altered with age. Descriptive indicators however are not enough to capture these changes. These complex interactions can only be deciphered using complexity-based methods such as approximate entropy and that too at the multiple scale level. [ABSTRACT FROM AUTHOR]

This paper presents a unified approach based on the recurrence quantification analysis (RQA) and approximate entropy (ApEn) for the classification of heart rate variability (HRV). In this paper, the optimum tolerance threshold (ropt) corresponding to ApEnmax has been used for RQA calculation. The experimental data length (N) of RR interval series (RRi) is optimized by taking ropt as key parameter. ropt is found to be lying within the recommended range of 0.1 to 0.25 times the standard deviation of the RRi, when N ≥ 300. Consequently, RQA is applied to the age stratified RRi and indices such as percentage recurrence (%REC), percentage laminarity (%LAM), and percentage determinism (%DET) are calculated along with ApEnmax, [Formula: see text], [Formula: see text], and an index namely the radius differential (RD). Certain standard HRV statistical indices such as mean RR, standard deviation of RR (or NN) interval (SDNN), and the square root of the mean squared differences of successive RR intervals (RMSSD) (Eur Hear J 17:354-381, 1996) are also found for comparison. It is observed that (i) RD can discriminate between the elderly and young subjects with a value of 0.1151 ± 0.0236 (mean ± SD) and 0.0533 ± 0.0133 (mean ± SD) respectively for the elderly and young subjects and is found to be statistically significant with p < 0.05. (ii) Similar significant discrimination was obtained using [Formula: see text] with a value of 0.1827 ± 0.0382 (mean ± SD) and 0.2248 ± 0.0320 (mean ± SD) (iii) other significant indices were found to be %REC, %DET, %LAM, SDNN, and RMSSD; however, ApEnmax was found to be insignificant with p > 0.05. The above features of RRi time series were tested for classification using support vector machine (SVM) and multilayer perceptron neural network (MLPNN). Higher classification accuracy was achieved using SVM with a maximum value of 99.71%. Graphical abstract. [ABSTRACT FROM AUTHOR]

Background: Gustilo IIIB tibial fractures are associated with high rates of infection and nonunion. This study evaluates the impact of factors such as patient demographics, mechanism of injury, time to the first debridement, and time to flap coverage on the union and infection rates. Materials and Methods: A retrospective analysis was performed on all patients with open tibial fractures who presented to our tertiary trauma center over 13 years from April 2000 to August 2013. All patients were followed for at least 6 months and continued till radiographic evidence of union (maximum 72 months). Time to fracture union was based on radiological evidence of callus bridging at least three cortices. Information on infection rates and the presence of microbes were evaluated. Results: A total of 120 patients were analyzed. The mean time to fracture union was 33.8 weeks. Younger age was associated with a lower risk of nonunion with the mean age being 30.4 years in union group compared to 38.2 in the delayed-union group. Smoking was associated with an increased risk of delayed union with revision surgery being needed in 61.5% of smokers compared to 36.4% in nonsmokers. Rates of infection were high at 30.3%. Smoking was associated with an increased risk of infection (65.4% vs. 24.7%). Conclusion: High-energy open tibia fractures required an average of 8.5 months to heal and delayed or nonunion at an earlier juncture cannot be assumed. [ABSTRACT FROM AUTHOR]

Purpose: The main objective was to compare post-operative outcomes in patients undergoing anterior cruciate ligament (ACL) reconstruction both with and without concomitant meniscus injury at a mean follow-up of 3.5 years. The secondary objective was to study the effect of different meniscal injury sites and treatment modalities on post-operative outcomes (PROS).Methods: This is a retrospective analysis of a prospectively maintained database of patients undergoing ACL reconstruction at our tertiary institution between 2009 and 2012. Age, sex, graft type, graft fixation modality, location of meniscal tear and treatment (meniscal repair or meniscectomy) were recorded in the database. PROS used included the Tegner activity scale and the Lysholm score.Results: There were no significant differences between patients with or without meniscal injury in terms of age, BMI or preoperative PROS. There was no significant difference in the post-operative outcome scores between patients with or without meniscal injury at a mean follow-up of 3.5 years. Regardless of the location of meniscal injury, the post-operative scores improved as compared to preoperative scores.Conclusion: Concomitant meniscal injury in cases of ACL reconstruction is not associated with poorer short-term post-operative PROS (mean follow-up time: 3.5 years). These findings may influence management decisions and help in preoperative counselling.Level Of Evidence: IV. [ABSTRACT FROM AUTHOR]

Attempts of clonal propagation of sugar maple through conventional and micropropagation techniques have been largely unsuccessful and the basis for this longstanding problem has remained unknown. Typical symptoms of stress in in vitro cultures of sugar maple and its intrinsic tolerance to highly shaded growing conditions indicated that optimization of light intensity might overcome its recalcitrance. To test this hypothesis we evaluated the growth, morphology, chlorophyll content and various chlorophyll fluorescence parameters of in vitro plantlets cultured under three intensities (4, 16 and 40 µmol m s) using two spectra of light (red-blue and full spectrum white). Higher light intensities increased fresh and dry mass, but had no significant effect on the number of nodes or plant height. Anthocyanin accumulation in tissues, reduction in chlorophyll content, and significantly increased physiological stress quantified by chlorophyll fluorescence parameters, indicated increasing levels of light induced damage to the tissues with increasing light intensities. The critical factor limiting sugar maple's response to in vitro propagation was light intensity and the levels commonly used for in vitro propagation are not suitable for sugar maple. The current study demonstrates the unique low light requirement, between 4 and 16 µmol m s, of this species to overcome the recalcitrance to in vitro propagation. Spectral differences in quality of light and its effect on in vitro growth and stress in cultures are also discussed. In general light induced stress symptoms begin to appear at lower intensities with RB spectrum as compared to the full spectrum lights. While this study is limited to maples, requirement of specific light intensity is likely the cause of recalcitrance in other woody species with similar ecological roles. [ABSTRACT FROM AUTHOR]

The cardioprotective effects of remote hind limb preconditioning (RIPC) are well known, but mechanisms by which protection occurs still remain to be explored. Therefore, the present study was designed to investigate the role of TRPV and CGRP in adenosine and remote preconditioning-induced cardioprotection, using sumatriptan, a CGRP release inhibitor and ruthenium red, a TRPV inhibitor, in rats. For remote preconditioning, a pressure cuff was tied around the hind limb of the rat and was inflated with air up to 150 mmHg to produce ischemia in the hind limb and during reperfusion pressure was released. Four cycles of ischemia and reperfusion, each consisting of 5 min of inflation and 5 min of deflation of pressure cuff were used to produce remote limb preconditioning. An ex vivo Langendorff's isolated rat heart model was used to induce ischemia reperfusion injury by 30 min of global ischemia followed by 120 min of reperfusion. RIPC demonstrated a significant decrease in ischemia reperfusion-induced significant myocardial injury in terms of increase in LDH, CK, infarct size and decrease in LVDP, +dp/dt and -dp/dt. Moreover, pharmacological preconditioning with adenosine produced cardioprotective effects in a similar manner to RIPC. Pretreatment with sumatriptan, a CGRP release blocker, abolished RIPC and adenosine preconditioning-induced cardioprotective effects. Administration of ruthenium red, a TRPV inhibitor, also abolished adenosine preconditioning-induced cardioprotection. It may be proposed that the cardioprotective effects of adenosine and remote preconditioning are possibly mediated through activation of a TRPV channels and consequent, release of CGRP. [ABSTRACT FROM AUTHOR]

Multiscale approximate entropy (MAE) is used to quantify the complexity of a time series as a function of time scale τ. Approximate entropy (ApEn) tolerance threshold selection 'r' is based on either: (1) arbitrary selection in the recommended range (0.1-0.25) times standard deviation of time series (2) or finding maximum ApEn (ApEn) i.e., the point where self-matches start to prevail over other matches and choosing the corresponding 'r' (r) as threshold (3) or computing r by empirically finding the relation between r, SD/SD ratio and N using curve fitting, where, SD and SD are short-term and long-term variability of a time series respectively. None of these methods is gold standard for selection of 'r'. In our previous study [], an adaptive procedure for selection of 'r' is proposed for approximate entropy (ApEn). In this paper, this is extended to multiple time scales using MAE and multiscale cross-MAE (XMAE). We applied this to simulations i.e. 50 realizations (n = 50) of random number series, fractional Brownian motion (fBm) and MIX (P) [] series of data length of N = 300 and short term recordings of HRV and SBPV performed under postural stress from supine to standing. MAE and XMAE analysis was performed on laboratory recorded data of 50 healthy young subjects experiencing postural stress from supine to upright. The study showed that (i) ApEn of HRV is more than SBPV in supine position but is lower than SBPV in upright position (ii) ApEn of HRV decreases from supine i.e. 1.7324 ± 0.112 (mean ± SD) to upright 1.4916 ± 0.108 due to vagal inhibition (iii) ApEn of SBPV increases from supine i.e. 1.5535 ± 0.098 to upright i.e. 1.6241 ± 0.101 due sympathetic activation (iv) individual and cross complexities of RRi and systolic blood pressure (SBP) series depend on time scale under consideration (v) XMAE calculated using ApEn is correlated with cross-MAE calculated using ApEn (0.1-0.26) in steps of 0.02 at each time scale in supine and upright position and is concluded that ApEn has highest correlation at most scales (vi) choice of 'r' is critical in interpreting interactions between RRi and SBP and in ascertaining true complexity of the individual RRi and SBP series. [ABSTRACT FROM AUTHOR]

Plant roots play an important adaptive role in drought prone environments. Although there have been many efforts to improve root traits to develop drought tolerant maize varieties but significant progress has not yet made mainly due to difficulty in screening root traits. The aims of the study were to develop an easy and reliable screening method for deep root mass and related root traits of maize in greenhouse and evaluate their association with the grain yield under water-deficit field conditions. Twelve maize hybrids and their corresponding 12 female inbred parents were evaluated for phenotypic variation in deep root mass (dry weight of the root section below 45 cm from the root base), and related root traits, such as root length and total root mass in PVC tubes in greenhouse. The test hybrids were selected based on their grain yield under water-deficit conditions in the field. Plants were grown in three different growing media, and a mixture of sand, vermiculite, perlite and soil was found to be the best growing medium to study root growth. Deep root mass, total root mass and root length differed significantly among the genotypes, and these traits showed positive relationship with grain yield under water-deficit field conditions. The root screening system used is simple and inexpensive, making it suitable for evaluating large number of maize genotypes for root traits in greenhouse for selection for drought tolerance. Several diverse inbred lines for deep root mass have been identified and these could be used as parents to develop appropriate populations to study the genetic basis of deep root mass with a goal to manipulate drought tolerance. [ABSTRACT FROM AUTHOR]

3-Substituted-2-oxazolidones are the key building blocks in the synthesis of many pharmaceutically important compounds and are capable of acting as chiral auxiliaries. Utilization of CO in the synthesis of valuable compounds is an important process in terms of synthetic challenges and environmental issues as CO is nontoxic, inexpensive, and highly abundant. We have studied the microcosmic mechanism of cycloaddition of N-substituted aziridines with CO assisted by catalyst 1,3-di-tert-butylimidazolium-2-carboxylate, which is a novel and versatile route for the production of 3-substituted-2-oxazolidones. The theoretical study at B3LYP/6-31g (d,p) level of DFT in gas phase as well as in solvent media of varying polarities rationalizes the experimental reactivity trends. Nucleophilic attack of CO moiety on N-benzylaziridine ring is identified as the rate-limiting step of the reaction. Based on the understanding of rate-limiting step, the study proposes an efficient alternate silicon-based catalyst for cycloaddition of N-substituted aziridines with CO to produce 3-substituted-2-oxazolidones Graphical abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Quaternary ammonium salt obtained from the Menshutkin reaction between DABCO and benzyl chloride has been used in the synthesis of a novel Bronsted acidic ionic liquid (IL), namely 1-benzyl-4-(sulfobutyl)-diaza-bicyclo-octane hydrogen sulfate. The reaction of DABCO with benzyl chloride is a crucial step in the synthesis of this IL. Density functional theory calculations at B3LYP/6-31G(d,p) level have been employed to investigate the mechanism of Menshutkin reaction by calculating the energy barriers through possible transition states i.e., five-membered ring transition state and S2 transition state in gas phase and in diethyl ether as a solvent. It was found that while DABCO reacts with benzyl chloride through the well-known S2 transition state mechanism, the corresponding reaction with chlorodiphenylmethane can proceed through both S2 and five-membered ring transition state mechanism. However, S2 transition state mechanism is still the strongly preferred one out of the two possible mechanisms. The electronic structure analysis shows that solvent effects and enhanced resonance stabilization may play a decisive role in guiding the reaction pathway. [ABSTRACT FROM AUTHOR]

The microcosmic mechanism of the Menshutkin reaction between DABCO and benzyl fluoride/fluorodiphenylmethane has been investigated in both the gas and solvent phase by performing DFT calculations at B3LYP/6-31G(d,p) level of theory. The Gibbs free energy profiles to reach the possible transition states, i.e., five-membered ring transition state and S2 transition state show that the reaction between DABCO and benzyl fluoride proceeds through S2 transition state in accordance with previously reported studies, while the reaction between DABCO and fluorodiphenylmethane proceeds through five-membered ring transition state contrary to earlier literature. The role of solvent has been elucidated by reoptimizing the structures using SMD model of solvation. Hydrogen bonding and steric hinderance have been identified as the key factors in guiding the reaction pathway of commercially important Menshutkin reaction. [ABSTRACT FROM AUTHOR]

Thirty five commercial maple syrups from twelve producers in Southern Ontario were evaluated for properties including light transmittance, autofluorescence, density, pH, total soluble solids (TSS), glucose and fructose content, total phenol content, antioxidant potential and mineral content (Mg, Mn, P, Zn, Ca, K, Fe and Pb). A high degree of variability was found in many characteristics, often exceeding an order of magnitude. Syrups were categorized based on light transmission at 560 nm into amber (12), dark (13) and very dark (10) using International Maple Syrup Institute (IMSI) guidelines. No statistical differences were found among grades of syrup for density, pH, TSS, glucose, fructose, total reducing sugars, glucose:fructose ratio, magnesium, manganese or potassium. Darker syrups showed significantly higher autofluorescence, total phenol content, antioxidant potential, phosphorous, calcium and total mineral content. Significant negative correlations of percent transmission with total phenol content, antioxidant potential and total mineral content are reported. Significant positive correlations among total phenol content, antioxidant potential and total mineral content are also described. The results from this study suggest that darker syrups tend to contain more beneficial traits and may be applied in developing functional foods and value added products. [ABSTRACT FROM AUTHOR]

An investigation was carried out to develop an efficient micropropagation protocol for Stevia rebaudiana Bertoni. Experiments were conducted to optimize suitable media for in vitro shoot multiplication and root induction and to study the effect of culture vessel on shoot multiplication. Out of the different media compared for in vitro shoot multiplication, hormone-free liquid medium was found the most suitable. The results also revealed that strength of Murashige and Skoog (MS) salt, culture medium consistency (solid or liquid) and type of culture vessel significantly influenced the in vitro shoot multiplication rate. The shoots when placed on half strength hormone free half MS medium and 100 ppm charcoal showed cent percent root induction with maximum number of roots per shoot (21.2) as well as maximum root length (4.22 cm). Hardening of rooted plants on biopeat showed more than 80 % of survival rate. Further, clonal fidelity of the in vitro raised plants was carried out using RAPD markers and results indicated that all the tissue cultured derived plants are true-to-type and there are no somaclonal variations among these plants. [ABSTRACT FROM AUTHOR]

RAPD (Random Amplified Polymorphic DNA) and ISSR (Inter-Simple Sequence Repeats) markers assay were employed to validate the genetic stability of date palm ( Phoenix dactylifera L.) plants multiplied through somatic embryogenesis with upto forty two in vitro subcultures. Out of the 160 RAPD and 21 ISSR primers screened, 30 RAPD and 12 ISSR primers produced a total of 347 (246 RAPDs + 101 ISSRs) clear, distinct and reproducible amplicons, which were monomorphic across all micropropagated plants (27) studied. Thus, a total 8592 bands (number of plants analysed x number of amplicons with all the primers) were generated which exhibited homogeneous banding patterns with both RAPD and ISSR markers. These results indicate that the micropropagation protocol developed by us for rapid in vitro multiplication is appropriate and suitable for clonal propagation of date palm and corroborated the fact that somatic embryogenesis can also be used as one of the safest modes for production of true-to-type plants. [ABSTRACT FROM AUTHOR]

Sarcomas of the breast are uncommon, accounting for less than 1% of all primary malignancies. Among these tumors, malignant fibrous histiocytoma (MFH) is very rare. One case of the MFH of the mammary gland is presented in this paper. A 20-year-old unmarried female presented with a left breast lump. Fine needle aspiration cytology was inconclusive. Biopsy revealed the diagnosis of malignant phylloides tumor. After simple mastectomy, histological diagnosis of MFH was made. In addition, the possibilities of the therapy of the MFH in the breast are discussed. [ABSTRACT FROM AUTHOR]

Reports on the case of a 24-year-old male with retroperitoneal accessory spleen. Detection of a vague mass in the left lumbar region; Observation of a retroperitoneal hypoechoic mass below the lower pole of the left kidney; Pattern of lymphoid tissue.