Constrained dynamics of a polymer ring enclosing a constant area

The dynamics of a polymer ring enclosing a constant {\sl algebraic} area is studied. The constraint of a constant area is found to couple the dynamics of the two Cartesian components of the position vector of the polymer ring through the Lagrange multiplier function which is time dependent. The time dependence of the Lagrange multiplier is evaluated in a closed form both at short and long times. At long times, the time dependence is weak, and is mainly governed by the inverse of the first mode of the area. The presence of the constraint changes the nature of the relaxation of the internal modes. The time correlation of the position vectors of the ring is found to be dominated by the first Rouse mode which does not relax even at very long times. The mean square displacement of the radius vector is found to be diffusive, which is associated with the rotational diffusion of the ring.Comment: 6 page

Self-consistent variational theory for globules

A self-consistent variational theory for globules based on the uniform expansion method is presented. This method, first introduced by Edwards and Singh to estimate the size of a self-avoiding chain, is restricted to a good solvent regime, where two-body repulsion leads to chain swelling. We extend the variational method to a poor solvent regime where the balance between the two-body attractive and the three-body repulsive interactions leads to contraction of the chain to form a globule. By employing the Ginzburg criterion, we recover the correct scaling for the $\theta$-temperature. The introduction of the three-body interaction term in the variational scheme recovers the correct scaling for the two important length scales in the globule - its overall size $R$, and the thermal blob size $\xi_{T}$. Since these two length scales follow very different statistics - Gaussian on length scales $\xi_{T}$, and space filling on length scale $R$ - our approach extends the validity of the uniform expansion method to non-uniform contraction rendering it applicable to polymeric systems with attractive interactions. We present one such application by studying the Rayleigh instability of polyelectrolyte globules in poor solvents. At a critical fraction of charged monomers, $f_c$, along the chain backbone, we observe a clear indication of a first-order transition from a globular state at small $f$, to a stretched state at large $f$; in the intermediate regime the bistable equilibrium between these two states shows the existence of a pearl-necklace structure.Comment: 7 pages, 1 figur

INDONESIAN STUDENT PERSPECTIVES ON A HUMANITY-BASED NATIONALISM

Do the Indonesian students revive the radical movements or do they have their own way in grasping nationalism in a globalized-world-perspective? How do they identify themselves as nation and how far they understand themselves the meaning of national solidarity? How effective their understanding on solidarity in the process of nation building? The aim of this study was to portray the perspectives of the Indonesian higher education students on nationalism. This study applied qualitative approach, by implementing series of Focus Group Discussion (FGD) and key informant interview (KII). Forty students of three private universities located in three provinces in Indonesia participated in six series of FGDs and three political figures play role as resource persons in the KIIs. The results of the study revealed that the students had three models of nationalism, that are, nationalism under the spirit of anticolonialism, nationalism under the national interests, and nationalism under the humanity perspectives

TLC Separation of Closely Related Amino Acids

761-76

SARS CoV-2 aggravates cellular metabolism mediated complications in COVID-19 infection.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the primary causative organism in corona virus disease-19 (COVID-19) infections, is a novel member of the human coronavirus family which was first identified in Wuhan, China, towards the end of 2019. This letter reveals new vital missing links in our current understanding of the mechanisms that lead to cell death triggered by ferroptotic stress in COVID-19 infection. It further reveal the importance of homocysteine mediated trans-sulfuration pathway in COVID-19 infection. Hence, Vitamin B6, folic acid, and Vitamin B12 should be incorporated in the treatment regimen for SARS CoV-2 infections to suppress complications, as the virus mediates altered host cell metabolism

Larvicidal activity of neem oil (Azadirachta indica) formulation against mosquitoes

<p>Abstract</p> <p>Background</p> <p>Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. <it>Azadirachta indica </it>(Meliaceae) and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes.</p> <p>Methods</p> <p>Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin) developed by BMR & Company, Pune, India, was evaluated against late 3^rdand early 4^thinstar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5–5.0 ppm) of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against <it>Anopheles</it>, <it>Culex</it>, and <it>Aedes </it>mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg <it>a.i</it>./m²to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper.</p> <p>Results</p> <p>Median lethal concentration (LC₅₀) of the formulation against <it>Anopheles stephensi</it>, <it>Culex quinquefasciatus </it>and <it>Aedes aegypti </it>was found to be 1.6, 1.8 and 1.7 ppm respectively. LC₅₀values of the formulation stored at 26°C, 40°C and 45°C for 48 hours against <it>Ae. aegypti </it>were 1.7, 1.7, 1.8 ppm while LC₉₀values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC₅₀and LC₉₀values of the formulation was observed against <it>Ae. aegypti </it>during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg <it>a.i</it>./m²in different breeding sites under natural field conditions provided 98.1% reduction of <it>Anopheles </it>larvae on day 1; thereafter 100% reduction was recorded up to week 1 and more than 80% reduction up to week 3, while percent reduction against <it>Culex </it>larvae was 95.5% on day 1, and thereafter 80% reduction was achieved up to week 3. The formulation also showed 95.1% and, 99.7% reduction of <it>Aedes </it>larvae on day 1 and day 2 respectively; thereafter 100% larval control was observed up to day 7.</p> <p>Conclusion</p> <p>The neem oil formulation was found effective in controlling mosquito larvae in different breeding sites under natural field conditions. As neem trees are widely distributed in India, their formulations may prove to be an effective and eco-friendly larvicide, which could be used as an alternative for malaria control.</p

Overcoming drug delivery barriers and challenges in topical therapy of atopic dermatitis: A nanotechnological perspective.

Atopic dermatitis (AD) is an inflammatory disorder centered around loss of epidermal barrier function, and T helper 2 (Th2) immune responses. The current understanding of disease heterogeneity and complexity, limits the rational use of existing topical, systemic therapeutic agents, but paves way for development of advanced therapeutic agents. Additionally, advanced nanocarriers that deliver therapeutics to target cells, seem to offer a promising strategy, to overcome intrinsic limitations and challenges of conventional, and traditional drug delivery systems. Ever-evolving understanding of molecular target sites and complex pathophysiology, adverse effects of current therapeutic options, inefficient disease recapitulation by existing animal models are some of the challenges that we face. Also, despite limited success in market translatibility, nanocarriers have demonstrated excellent preclinical results and have been extensively studied for AD. Detailed research on behavior of nanocarriers in different patients and tailored therapy to account for phenotypic variability of the disease are the new research avenues that we look forward to

Efektivitas Penggunaan Aplikasi Wordwall dalam Pembelajaran IPS Secara Daring (Online) di Kelas Tinggi Sekolah Dasar

Situasi pandemi Covid-19 mengubah pembelajaran tatap muka di kelas menjadi pembelajaran daring (online). Media pembelajaran online yang menjamin keutuhan kegiatan pembelajaran serta mengangkat motivasi dan fokus peserta didik adalah aplikasi Wordwall. Masalah penelitian adalah ‘Bagaimana efektivitas penggunaan media wordwall pada kegiatan pembelajaran IPS secara daring di kelas tinggi SD?”, Penelitian bertujuan melihat efektivitas penggunaan media wordwall pada kegiatan pembelajaran IPS secara daring di kelas tinggi SD. Penelitian ini adalah jenis Mixed Method. Analisis data menggunakan analisis kuantitatif pada angket dan tes, analisis kualitatif pada wawancara. Subjek penelitian adalah peserta didik&nbsp; kelas tinggi SDK Canosa. Hasil penelitian menunjukan rata-rata kelas hasil belajar IPS peserta didik&nbsp; kelas tinggi adalah sebesar&nbsp; 79.99. Ditinjau dari KKM 70, maka diketahui 55 dari 58 (94.83%) orang peserta didik&nbsp; tuntas, 3 orang (5.20%) tidak tuntas. Angket menunjukkan tingkat capaian responden (peserta didik ) sebesar 91.90% atau sangat efektif, hasil wawancara kepala sekolah dan guru mengindikasikan peserta didik&nbsp; terlibat secara aktif dalam pembelajaran dan antusias mengerjakan kuis-kuis, menggabungkan kata, menemukan kata, dan melakukan game