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Microfluidic systems with integrated sensors are ideal platforms to study and emulate processes such as complex multiphase flow and reactive transport in porous media, numerical modeling of bulk systems in medicine, and in engineering. Existing commercial optical fibre sensing systems used in integrated microfluidic devices are based on single-core fibres, limiting the spatial resolution in parameter measurements in such application scenarios. Here, we propose a multicore fibre-based pH system for in-situ pH mapping with tens of micrometer spatial resolution in microfluidic devices. The demonstration uses custom laser-manufactured glass microfluidic devices (called further micromodels) consisting of two round ports. The micromodels comprise two lintels for the injection of various pH buffers and an outlet. The two-port system facilitates the injection of various pH solutions using independent pressure pumps. The multicore fibre imaging system provides spatial information about the pH environment from the intensity distribution of fluorescence emission from the sensor attached to the fibre end facet, making use of the cores in the fibre as independent measurement channels. As proof-of-concept, we performed pH measurements in micromodels through obstacles (glass and rock beads), showing that the particle features can be clearly distinguishable from the intensity distribution from the fibre sensor. [ABSTRACT FROM AUTHOR]

Long-chain organic molecules, 1-halododecane, RX (X=Cl,Br), adsorbed on Si(111)-7×7 were shown to form stable dimeric corrals; type I around corner holes and type II around corner adatoms S. Dobrin et al. [Surf. Sci. Lett. 600, L43 (2006)]. Here we examine the molecular dynamics of corral formation, in which mobile physisorbed adsorbates spontaneously convert to immobile. At high coverage the mechanism gives evidence of involving collisions between mobile vertical monomers, giving types I and II immobile horizontal dimers, vD+vD→h2 (I, II). At low coverage mobile vertical monomers collide with immobile horizontal ones to form largely type-II corrals, vD+h→h2 (II). Thermal reaction of corrals with X=Br brominates the surface by two distinct molecular pathways, thought to have more general applicability: “daughter-mediated” reaction of vertical vA with a low activation energy (here Ea∼5 kcal mol-1) and “parent-mediated” reaction of horizontal h or h2 with high activation energy (here Ea=29 kcal mol-1). [ABSTRACT FROM AUTHOR]

This paper presents an Oxyrrhis Marina-inspired search and dynamic formation control (OMS-DFC) framework for multi-unmanned aerial vehicle (UAV) systems to efficiently search and neutralize a dynamic target (forest fire) in an unknown/uncertain environment. The OMS-DFC framework consists of two stages, viz., the target identification stage without communication between UAVs and the mitigation stage with restricted communication. In the first stage, each UAV adapts proposed OMS with three levels to select between Levy flight, Brownian search, and directionally driven Brownian (DDB) search for accurate target identification (“fire location”). The selection of each level is based on the available sensor information about the possible fire location. In the second stage, the UAVs that identified a fire location fly in a dynamic formation to quench the fire using water. The proposed formation is achieved through decentralized control, where a UAV computes the control action based on the fire profile and also the angular position and angular separation with its succeeding neighbor. The proposed formation control law guarantees asymptotic convergence to the desired time-varying angular position profile of UAVs based on the nature of fire spread (circular/elliptical). To evaluate the performance of the proposed OMS-DFC for the multi-UAV system, a search and fire quenching mission in a typical pine forest is simulated. A Monte Carlo simulation study is conducted to evaluate the average performance of the proposed OMS-DFC-based multi-UAV mission, and the results clearly highlight the advantages of the proposed OMS-DFC in forest firefighting. Note to Practitioners—Searching and mitigating dynamic targets like the forest fire is a challenging task due to the large area involved and also the time-varying nature of fire spread. The use of a cooperative multi-unmanned aerial vehicle (UAV) system for searching targets in large area poses difficulties in maintaining persistent long distance communication between them. Moreover, the elliptical fire profile demands a time-varying angular displacement formation control of UAVs for effective fire mitigation. In this paper, we present a two-stage framework for search and mitigation of forest fire. The first stage provides a decentralized, noniterative stochastic search algorithm that requires no information sharing between the UAVs. The proposed search algorithm can be implemented without much computational efforts using a temperature measuring sensor and a thermal imaging sensor. The second stage provides a decentralized time-varying angular displacement formation control law efficient for tracking elliptical targets. The formation control law only assumes the availability of restricted UAV communication. The proposed formation control law can handle any targets that demand time-varying angular displacement formation for UAVs. The proposed algorithm is suitable for multi-UAV missions involving search and mitigation of dynamic targets distributed over a large area. [ABSTRACT FROM AUTHOR]

An efficient in vitro mass multiplication protocol was developed for selected species of screw pine ( Pandanus fascicularis Lam. , P. furcatus Roxb.). The protocol could be successfully used for large scale production of planting materials leading to cultivation and making bio-fences or green belts in coastal areas, wetlands for protection and preventing soil erosion. This will facilitate the replenishment of the bio resource and also provide good breeding space for various fauna associated with it. For developing the tissue culture protocol, shoot tips and tillers from the mature plants were used as the explants. Surface sterilization with 0.1 % mercuric chloride for 1 min. Yielded good fraction (65 %) of contamination free explants. Explants inoculated in MS solid medium supplemented with 6-benzylaminopurine (BAP, 2.5 mg/l) and indole-3-acetic acid (IAA, 0.5 mg/l), induced 2-3 shoot buds in 5 weeks. These buds either individually or along with the explant portion, sub-cultured to fresh media containing the same hormonal combinations, resulted induction of 5-6 shoot buds in 4 weeks. Repeated subcultures of shoot buds in the same medium produced 8-10 shoot buds in every 4 weeks. Shoot elongation was achieved (~ 3 cm) by transferring the shoot clusters or individual shoots to basal medium, and the elongated shoots were rooted in vitro or ex vitro. Root induction in shoots (87.4 %) was achieved in MS medium supplemented with 0.1 mg/l indole-3-butyric acid (IBA). Rooted shoots were established in paper/polythene cups filled with fine sand, which subsequently recorded 85 % establishment under the shade-net house with proper irrigation. Plants grown in poly-bags were later successfully established in different field conditions and recorded 100 % survival. [ABSTRACT FROM AUTHOR]

The recoil of adsorbates away (desorption) and towards (reaction) surfaces is well known. Here, we describe the long-range recoil of adsorbates in the plane of a surface, and accordingly the novel phenomenon of reactions occurring at a substantial distance from the originating event. Three thermal and three electron-induced surface reactions are shown by scanning tunnelling microscopy to propel their physisorbed ethylenic products across the rough surface of Si(100) over a distance of up to 200 Å before an attachment reaction. The recoil energy in the ethylenic products comes from thermal exoergicity or from electronic excitation of chemisorbed alkenes. We propose that the mechanism of migration is a rolling motion, because the recoiling molecule overcomes raised surface obstacles. Electronic excitation of propene causes directional recoil and often end-to-end inversion, suggesting cartwheeling. Ab initio calculations of the halogenation and electron-induced reactions support a model in which asymmetric forces between the molecule and the surface induce rotation and therefore migration. [ABSTRACT FROM AUTHOR]

The controlled imprinting of surfaces with specified patterns is important in the development of nanoscale devices. Previously, such patterns were created using self-assembled physisorbed adsorbate molecules that can be stabilized on the surface by subsequent chemical bonding. Here we show a first step towards use of the bonding within a surface to propagate reactions for patterning, namely the cooperative reaction of adjacent silicon atoms. We exploit the double-bonded silicon dimer pairs present on the surface of Si(100)-2×1 and show that the halogenation of one silicon atom (induced by electrons or heat) results in cooperative halogenation of the neighbouring silicon atom with unit efficiency. The reactants used were two 1-halopentane molecules physisorbed over a pair of silicon atoms. This cooperative pair of halogenation reactions was shown by ab initio calculation to be sequential on a timescale of femtoseconds. [ABSTRACT FROM AUTHOR]

One-dimensional nanostructures at silicon surfaces have potential applications in nanoscale devices. Here we propose a mechanism of dipole-directed assembly for the growth of lines of physisorbed dipolar molecules. The adsorbate chosen was a halide, in preparation for the patterned imprinting of halogen atoms. Using scanning tunnelling microscopy, physisorbed 1,5-dichloropentane on Si(100)-2×1 was shown to self-assemble at room temperature into molecular lines that grew predominantly perpendicular to the Si-dimer rows. Line formation was triggered by the displacement of surface charge by the dipolar adsorbate. Experimental and simulated scanning tunnelling microscopy images were in agreement for a range of positive and negative bias voltages. The geometry of the physisorbed molecules and nature of their binding were evident from the scanning tunnelling microscopy images, as interpreted by scanning tunnelling microscopy simulation. [ABSTRACT FROM AUTHOR]

Scanning tunneling microscopy (STM) has been used to study the adsorption of 1-fluoro-, 1-chloro-, and 1-bromo-substituted C12 alkanes at the Si(111)-7 × 7 surface, at temperatures from 300 to 500 K. We report self-assembly of these physisorbed adsorbates, C12H25X, to form approximately circular corrals, (C12H25X)2, with charge transfer to a corralled adatom in each case (cf. Dobrin et al. Surf. Sci.2006, 600, L43). The corrals comprised pairs of semicircular horizontal long-chain molecules stable to ∼100 °C. At ≥150 °C, the corrals desorbed or reacted locally to imprint a halogen atom, X−Si, and an adjacent alkane residue, R−Si. The corral height profiles, together with the location of the imprinted X−Si resulting from thermal or electron-induced surface reaction, led to a picture of the molecular configurations in these haloalkane corrals, (C12H25X)2, X = F, Cl, Br, and the dichloro corrals, 1,12-dichlorododecane, (ClC12H24Cl)2. [ABSTRACT FROM AUTHOR]

Abstract: Thermal reactions of 1,2- and 1,4-dibromoxylene (1,2- and 1,4-diBrXy) with Si(111)-7×7 were investigated by STM at room temperature under UHV conditions. Reaction led to the formation of single adsorbed Br-atoms or pairs of Br-atoms, in a ratio approx. 3:1 for both reagents. Experimental results were interpreted in terms of ‘parent-mediated’ (halogen atom accompanied by organic residue), and ‘daughter-mediated’ (no accompanying organic residue) reaction dynamics. Both mechanisms contributed to the bromination of the silicon surface in comparable amounts. For pairs of bromine atoms the Br–Br separation had a most probable value of 7.6Å for 1,2-diBrXy, and 11.5Å for 1,4-diBrXy. This separation was in each case greater than that in the diBrXy parent molecule by a few angstroms. For parent-mediated reaction the dynamics were revealed in detail by the STM images which gave the vectorial location of the halogen-atom products (distance and angle of the daughter atoms) relative to the prior location and alignment of the adsorbed parent molecule. Both reagents, 1,2- and 1,4-diBrXy, were found to be less reactive than the corresponding dibromobenzenes studied earlier in this laboratory [S. Dobrin et al., Surf. Sci. 561 (2004) 11], in both parent- and daughter-mediated modes. [Copyright &y& Elsevier]

We report a first attempt, using AM1, to model the thermal reaction of 1,2- and 1,4-dibromobenzene with a Si(111)-7×7 surface, a reaction recently studied experimentally by scanning tunneling microscopy (STM) [S. Dobrin et al., Surf. Sci. 561 (2004) 11]. As postulated on the basis of the experimental findings, two generalizable types of reaction pathways are found to be open. The indirect, ‘Parent-mediated’, dynamics involves prior attachment of the parent molecule by (in the present case) its benzene ring to the surface, followed by detachment of one or two bromine atoms from the ring, R, which most often remains attached to the surface. This results in formation of a single Br–Si or a pair or Br–Si with, in each case, an adjacent feature, R–Si. The alternate ‘Daughter-mediated’ pathway involves the direct approach of the reactive daughter Br-atoms to the Si surface to form the same products without, generally, leaving an organic residue, R–Si, at the surface. The calculated activation energies for successive bromination of the surface by either the Parent-mediated (P) or Daughter-mediated (D) pathways were found to lie in the range 0.7–1.27eV, consistent with the observation of thermal reaction of the title molecules to give both single Br–Si and pairs of Br–Si at room temperature by either mechanism. Activation energies for bromination by P or D are less than the bond-dissociation energies for the C–Br bond being broken, since Br–Si bond-formation occurs concurrently with bond breaking. The old C–Br bond extends to form the new Br–Si, so that Br–Si imprints at the surface have a wider mean separation than do the Br substituents in the parent, as well as a wider mean separation for Br–Si when they come from 1,4- than from 1,2 dibromobenzene. This agrees with observation. In Daughter-mediated reaction the adsorbate is postulated to approach laterally, ‘stamping’ a characteristic narrow Br⋯Br separation or ‘rocking’ to imprint the wider separations observed. [Copyright &y& Elsevier]

A comparative study is reported of the thermal reaction of 1,2- and 1,4-dibromobenzene (1,2- and 1,4-diBrPh) on Si(1 1 1)-7 × 7, investigated by STM. Some results are given for the intermediate case of 1,3-diBrPh. The STM images gave evidence of a different pattern of reaction to yield pairs of Br–Si for 1,2-, 1,3- and 1,4-diBrPh. The ratio of pairs of Br–Si to single bromination events was 1:2 for 1,2-diBrPh and 1:3 for 1,4-diBrPh. In many cases organic residue from the bromination reaction, R–Si, was evident in the STM image. The products R–Si and Br–Si were found to be bound to adjacent Si, for both 1,2- and 1,4-diBrPh. The mean Br⋯Br pair separation at the surface depended on the parent molecule, being 7.6 Å for 1,2-diBrPh, 10.3 Å for 1,3-diBrPh, and 11.3 Å for 1,4-diBrPh. These separations are, in each case, about 4 Å greater than the separation of the Br-atoms in the intact parent molecule, which increases systematically down the series. There was a marked decrease in the percentage of R–Si accompanying the Br–Si in going down the series, decreasing from 70% for 1,2- to 20% for 1,4-diBrPh; this was interpreted as being due to a decrease in the percentage of `benzene-mediated'' reaction dynamics, in which the benzene ring was bound to the surface. At moderately increased surface temperature (45 °C) the reaction of 1,2- and also 1,4-diBrPh no longer resulted in R–Si formation, suggesting that the dynamics had altered from benzene-mediated to `bromine-mediated''. [Copyright &y& Elsevier]

Chloropentane forms asymmetric (‘A’) and symmetric (‘S’) pairs on Si(100)-2×1, differing in the direction of curvature of one pentane tail. Surprisingly this renders the rate of thermal reaction of ‘A’ fifteen times greater than ‘S’ in chlorinating room-temperature silicon. Correspondingly, for electron-induced reaction the energy threshold for Ais 1 eV less than for S. [ABSTRACT FROM AUTHOR]

The current coronavirus disease (COVID-19) pandemic is showing no signs of abatement and result in significant morbidity and mortality in the infected patients. Many therapeutic agents ranging widely between antivirals and anti-inflammatory drugs have been used to mitigate the disease burden. In the deluge of the drugs being used for COVID-19 infection, glucocorticoids (GCs) stand out by reducing mortality amongst in-hospital severe-to-critically ill patients. Health-care practitioners have seen this as a glimmer of hope and started using these drugs more frequently than ever in clinical practice. The fear of mortality in the short term has overridden the concern of adverse long-term consequences with steroid use. The ease of availability, low cost, and apparent clinical improvement in the short term have led to the unscrupulous use of the steroids even in mild COVID-19 patients including self-medication with steroids. The use of GCs has led to the increasing incidence of hyperglycemia and consequent acute complications of diabetic ketoacidosis and mucormycosis in COVID-19 patients. There is an urgent need to dissipate information about optimum management of hyperglycemia during steroid use. In view of this, the Endocrine Society of India has formulated this position statement about the diagnosis and management of hyperglycemia due to the use of GCs in patients with COVID-19 infection. [ABSTRACT FROM AUTHOR]

Global warming and endocrine disorders are intertwined issues posing significant challenges. Greenhouse gases emanating from human activities drive global warming, leading to temperature rise and altered weather patterns. South Asia has experienced a noticeable temperature surge over the past century. The sizable population residing in the region heightens the susceptibility to the impact of global warming. In addition to affecting agriculture, water resources, and livelihood, environmental changes interfere with endocrine functioning. Resulting lifestyle changes increase the risk of metabolic and endocrine disorders. Individuals with diabetes face heightened vulnerability to extreme weather due to impaired thermoregulation. A high ambient temperature predisposes to heat-related illnesses, infertility, and nephropathy. Additionally, essential endocrine drugs and medical devices are susceptible to temperature fluctuations. The South Asian Federation of Endocrine Societies (SAFES) calls for collaboration among stakeholders to combat climate change and promote healthy living. Comprehensive approaches, including the establishment of sustainable food systems, promotion of physical activity, and raising awareness about environmental impacts, are imperative. SAFES recommends strategies such as prioritizing plant-based diets, reducing meat consumption, optimizing medical device usage, and enhancing accessibility to endocrine care. Raising awareness and educating caregivers and people living with diabetes on necessary precautions during extreme weather conditions are paramount. The heat sensitivity of insulin, blood glucose monitoring devices, and insulin pumps necessitates proper storage and consideration of environmental conditions for optimal efficacy. The inter-connectedness of global warming and endocrine disorders underscores the necessity of international collaboration guided by national endocrine societies. SAFES urges all stakeholders to actively implement sustainable practices to improve endocrine health in the face of climate change. [ABSTRACT FROM AUTHOR]

For the nonlinear equations of motion of the nano air vehicle, including the gyroscopic coupling and countertorque generated by the propulsion system, a linear state-space model is developed for analyzing the effects of gyroscopic coupling and countertorque on the dynamic behavior of the nano air vehicle. By analyzing the trajectories of eigenvector components obtained by increasing the gyroscopic coupling, it is shown that the different modes of the nano air vehicle influence both the lateral and longitudinal variables, thereby losing the conventional characteristics of these modes. The investigation shows that the stability of the coupled phugoid and coupled Dutch roll modes are improved, whereas the stability of the coupled spiral, coupled roll subsidence, and coupled short-period modes are degraded with the enhancement of gyroscopic coupling. Concurrently, increasing the gyroscopic coupling increases the damping ratio of the coupled Dutch roll and coupled phugoid modes. In contrast to this, the gyroscopic coupling reduces the damping ratio of the coupled short-period mode. The frequency of the coupled phugoid and coupled short-period modes is also increased with the increment in the gyroscopic coupling. The analysis also indicates that the countertorque destabilizes the coupled spiral mode. [ABSTRACT FROM AUTHOR]

The article presents an abstract of a research study which examines the effect of disulfide and sulfhydryl group modification on the binding activity of 5-HTIA receptor for agonist and antagonist. Under the study, the 5-UTIA receptors from bovine hippocampal membranes were exposed to L-dithiothreitol or N-ethylmaleirnide and ligand binding was monitored.

Objective: To study pregnancy outcomes in relation to thyroid peroxidase antibody (TPOAb) status with optimum thyroxine replacement for subclinical hypothyroidism. Materials and Methods: Ninety-eight women with subclinical hypothyroidism were followed up until the end of their pregnancy. TPO antibody status was performed for 59 women (positive 20, negative 39). Levothyroxine was supplemented to maintain TSH between 0.3-3 mIU/l in all patients, irrespective of TPOAb status. Pregnancy outcomes were noted as pregnancy-induced hypertension (PIH), antepartum or postpartum hemorrhage, preterm delivery, and spontaneous abortion. Outcomes were compared between 3 groups as per TPO antibody status (positive, negative, and undetermined), which were matched for age and gestational period. Results: Thyroid autoimmunity was noted in 34% of women screened for TPO antibody. A total of 11 adverse pregnancy outcomes were recorded (4 spontaneous abortions, 4 preterm deliveries, 3 PIH) with no significant difference between the groups. Conclusion: Adverse pregnancy outcomes were not different in the 3 groups with adequate thyroxine replacement for pregnant women with subclinical hypothyroidism targeting TSH in euthyroid range, irrespective of thyroid autoimmunity status. [ABSTRACT FROM AUTHOR]

In this article, we propose a bilevel segmentation framework with metacognitive learning (BS-McL) to detect power lines with an RGB camera mounted on an unmanned aerial vehicle (UAV) platform. The proposed framework consists of two levels based on spectral and spatial techniques. In the first level, spectral classification is carried out using the McL method, which is an evolving online learning neural network architecture. Due to similarities in spectral intensities, few nonpower line pixels are grouped along with power line pixels. The nonpower line pixels are removed by spatial segmentation in the second level. The second level includes morphological operations such as geometric features (shape and density indices), which are applied to detect the power lines. The processing steps of BS-McL are illustrated using a synthetic image of size $9 \times 6$ pixels. Also, two datasets consisting of 64 images with varying backgrounds, different locations, and dimensions of power lines are used to demonstrate the performance of the proposed BS-McL. The obtained results for BS-McL are compared with five commonly used methods. For both datasets, the efficiency of the BS-McL for power line extraction is better than for the methods used for comparison. Furthermore, the trained knowledge from our experimental set-up (Dataset 1: suburban scene) can be transferred to another dataset that is available publicly (Dataset 2: urban and mountain scenes) if the power line spectral values are in relevance with the distribution in the training dataset. The proposed approach BS-McL is based on online learning with a self-adaptive architecture, which provides improved generalization ability. [ABSTRACT FROM AUTHOR]