Infinite bound states and $1/n$ energy spectrum induced by a Coulomb-like potential of type III in a flat band system

In this work, we investigate the bound states in a one-dimensional spin-1 flat band system with a Coulomb-like potential of type III, which has a unique non-vanishing matrix element in basis $|1\rangle$. It is found that, for such a kind of potential, there exists infinite bound states. Near the threshold of continuous spectrum, the bound state energy is consistent with the ordinary hydrogen-like atom energy level with Rydberg correction. In addition, the flat band has significant effects on the bound states. For example, there are infinite bound states which are generated from the flat band. Furthermore, when the potential is weak, the bound state energy is proportional to the potential strength $\alpha$. When the bound state energies are very near the flat band, they are inversely proportional to the natural number $n$ (e.g., $E_n\propto 1/n, n=1,2,3,...$). Further we find that the energy spectrum can be well described by quasi-classical approximation (WKB method). Finally, we give a critical potential strength $\alpha_c$ at which the bound state energy reaches the threshold of continuous spectrum. After crossing the threshold, the bound states in the continuum (BIC) would exist in such a flat band system.

Dynamic climate clubs: On the effectiveness of incentives in global climate agreements

A proposal to combat free riding in international climate agreements is the establishment of a climate club—a coalition of countries in a structure to encourage high levels of participation. Empirical models of climate clubs in the early stages relied on the analysis of single-period coalition formation. The earlier results suggested that there were limits to the potential strength of clubs and that it would be difficult to have deep abatement strategies in the club framework. The current study extends the single-period approach to many periods and develops an approach analyzing “supportable policies” to analyze multiperiod clubs. The major element of the present study is the interaction between club effectiveness and rapid technological change. Neither alone will produce incentive-compatible policies that can attain the ambitious objectives of international climate policy. The trade sanctions without rapid technological decarbonization will be too costly to produce deep abatement; similarly, rapid technological decarbonization by itself will not induce deep abatement because of country free riding. However, the two together can achieve international climate objectives.

Architectural Heritage Conservation in Nigeria: The Need for Innovative Techniques

Architectural heritage conservation in recent years has hinged on conventional methods and has failed to recognize innovative methods and emerging technologies. Consequently, in Nigeria, suboptimal conservation work results in the continual deterioration of architectural heritage, leading to the loss of heritage and its values and significance. The study, therefore, sought to examine challenges and prospects for implementing innovative techniques in the conservation of architectural heritage in Nigeria. The study examined three heritage conservation interventions in Nigeria, focusing on the applicability of innovative conservation methods for documentation, diagnosis, and treatment of deterioration of architectural heritage. Questionnaires were administered through purposive sampling to 40 heritage conservation professionals, with 31 (77.5%) completed and returned for analysis. A Cronbach’s alpha reliability test value of 0.76 established the validity of the research instrument. The findings affirmed that heritage professionals have low familiarity (mean value of 2.19) with innovative techniques for conservation of architectural heritage. Of the respondents, 41.9% had gained a minimal level of technical knowledge of how to implement innovative techniques in conservation interventions. Improving the performance of conservation interventions also ranked highly as a potential strength of implementing innovative techniques. Conclusively, there is a need to improve advocacy and training in innovative conservation techniques based on their ability to characterize architectural heritage materials and investigate their chemical composition, microstructure, and morphological features.

PERANG KESULTANAN ARU MENGHADAPI KESULTANAN ACEH DI ABAD XVI M

Aru Sultanate was a state in Sumatra Island cited by numerous local and international sources between 13th and 16th centuries CE. In the middle of 16th century CE, the sovereignty of Aru was threatened by Aceh Sultanate’s aggression to its neighbouring states in Sumatra. Aru Sultanate’s strategic moves to deal with that aggression is the subject matter of this article. The discussion of such strategies is aimed at revealing what options came to surface by the defensive side to counter the aggressor. Historical reviews of two main records of the Portuguese Tomé Pires and Ferna-O Mendes Pinto revealed the potential strength and strategies adopted by Aru Sultanate to repel Aceh Sultanate’s attack. The presence of the fort as a supporting defensive factor allows Aru Sultanate to deploy a defensive strategy in Aru War I. The defensive stance, however, turned into offensive one in Aru Wars II and III as a strong ally, Johor Sultanate came to assist. Despite more alliances were formed with more states, victory ultimately belonged to Aceh Sultanate. Kesultanan Aru adalah salah satu negeri di Pulau Sumatera yang disebut oleh sumber-sumber tertulis lokal dan mancanegara sejak abad ke-13 – ke-16 M. Pada pertengahan abad ke-16 M, kedaulatan Kesultanan Aru terancam oleh agresi Kesultanan Aceh ke negeri-negeri tetangganya di Pulau Sumatera. Langkah-langkah strategis apa yang ditempuh oleh Kesultanan Aru dalam menghadapi agresi Kesultanan Aceh, merupakan permasalahan yang diulas dalam karya tulis ini. Pembahasan tentang strategi yang dipakai oleh Kesultanan Aru dalam menghadapi agresi Kesultanan Aceh bertujuan mengungkap pilihan strategi yang diterapkan oleh pihak yang bertahan dalam menghadapi agresi dari luar. Melalui kajian historis terhadap data utama berupa dua catatan bangsa Portugis yakni Tome Pires dan Ferna-O Mendes Pinto, diungkap potensi kekuatan dan strategi yang diterapkan oleh Kesultanan Aru dalam menghadapi serangan Kesultanan Aceh. Keberadaan benteng sebagai salah satu unsur kekuatan negara, membuat Kesultanan Aru memilih strategi yang defensif pada Perang Aru I. Strategi Kesultanan Aru berubah dari defensif menjadi ofensif -saat Perang Aru II dan Perang Aru III- setelah memperoleh sekutu yang kuat yakni Kesultanan Johor. Meskipun jalinan persekutuan telah dibentuk oleh Kesultanan Aru dengan sejumlah negeri, namun kejayaan akhirnya menjadi milik Kesultanan Aceh.

The Climax of the Seleucid-Parthian Rivalry

This chapter focuses on the contexts and consequences of the last great Seleucid campaign in the Middle East. The new rivalry of the Seleucids and Parthians was highly volatile. Yet the potential strength of the Seleucid state remained considerable under a strong ruler. The enthusiastic Seleucid king, Antiochus VII, became determined to reestablish the undisputed power of the Seleucid Empire throughout Mesopotamia and the Iranian plateau. His grand campaign against the Parthians in the early 120s was the greatest threat to the survival of the Parthian state since the campaign of Antiochus III almost a century before. Unfortunately for the Seleucids, it also culminated in the greatest defeat in their history. With their decisive victory, the Parthians were poised to push their advantage against the Seleucids into the lands of the Near East for the first time. However, a near catastrophic series of nomadic invasions along the eastern frontier of the Parthian Empire demanded the full attention of the Parthians. Once more the Parthians faced a considerable threat to the survival of their state as they suffered multiple severe defeats in their efforts to repulse nomadic incursions into the Iranian plateau. It was not until arguably the greatest of the Parthian monarchs, Mithridates II, became the new leader of the Parthians that they emerged as a world power.

Children in Greek Tragedy

Astyanax is thrown off the walls of Troy, Medeia kills her children to take revenge on her husband, and Aias reflects sadly on his son’s inheritance, yet he kills himself and leaves Eurysakes vulnerable to his enemies. The pathos created by threats to children is a notable feature of Greek tragedy, but does not explain the range of situations where the playwrights chose to employ them. Although they are largely silent, passive figures, children exert a dramatic force that goes beyond their limited onstage presence. This book proposes a new paradigm to understand the roles of children in tragedy, emphasizing their dangerous potential as the future adults of myth. Their multiple projected lives create dramatic palimpsests which are paradoxically more significant than the immediate emotional effects. Children are never killed because of their immediate weakness, but because of their potential strength. Staging considerations underpin this re-evaluation, as the embodied identities of children are central to their roles. A new examination of the evidence for child actors concludes that the physical presence of children was a significant factor in their presentation. The socio-historical context of fifth-century Athens gives some pointers, but child roles can only be fully appreciated as theatrical phenomena, utilizing the inherent ambiguities of drama.

Insights into RNA-dependent RNA Polymerase Inhibitors as Anti-influenza Virus Agents.

Background: Influenza is a seasonal disease which affects millions of people every year and has a significant economic impact. Vaccines are the best strategy to fight this viral pathology, but they are not always available or administrable, prompting the search for antiviral drugs. RNA-dependent RNA polymerase (RdRp) recently emerged as a promising target, because of its key role in viral replication and its high conservation among viral strains. Discussion: This review presents an overview of the most interesting RdRp inhibitors that have appeared in the literature since 2000. Compounds already approved or in clinical trials and a selection of inhibitors endowed with different scaffolds are described, along with the main features responsible for their activity. Results: RdRp inhibitors are emerging as a new strategy to fight viral infections, and the importance of this class of drugs has been confirmed by the FDA approval of baloxavir marboxil in 2018. Despite the complexity of the RdRp machine makes the identification of new compounds a challenging research topic, it is likely that in the coming years this field will attract the interest of a number of academic and industrial scientists because of the potential strength of this therapeutic approach.

Unmanned Ariel Vehicle Sorts with Societal and Security Applications

The goal this paper aims to detail exploration about the Unmanned Ariel Vehicle and its types and various application use cases of its. Discuss the Unmanned Ariel Vehicle market growth and regulations. Unmanned Arial Vehicle – generally called as UAV are the cutting edge technology and buzz word in the recent years because of its various potential strength. UAVs are usually called as Drone. As the name implies UAV is the aircraft without a human pilot on the board. Drones are controlled from the ground control system (GCS) or designed to fly autonomously using the defined flight path and flight plan.

Wettability Transition of a Liquid Droplet on Solid Surface With Nanoscale Inverted Triangular Grooves

Inspired by a few phenomena in nature such as the lotus leaf, red rose petal, gecko’s feet and Nepenthes Alata plant, much attention has been paid to use simple and feasible means to achieve remarkable wetting behaviour for many applications in various areas including self-cleaning for building exteriors and windshields, oil/water separation, anti-icing, liquid collecting, anti-fogging and anti-corrosion. Based on the established theoretical models, wetting behaviour of a liquid droplet obtained by molecular dynamics simulation method is generally in good agreement with the experimental results. In macro and micro scale, the previous theories can explain and predict the wetting behaviors well. However, these theories are invalid for nanoscale. It is essential to reveal the underlying physical mechanism of the wetting behaviors of the droplet on solid surface with nanoroughness. Extensive studies on nanosale wettability focus on the effect of nano structures on wettability state. Desired wetting behavior of rough material surface achieved by nanosize reentrant geometry like “T” or mushroom shape and other variant geometry with solid overhangs has been widely used in self-cleaning surfaces, heat exchange and many applications. For example, “T” shape groove with different depths and widths under nanoscale has been considered to confer superhydrophobicity to hydrophilic surfaces gradually. In this paper, wettability transition of a liquid droplet on geometrically heterogeneous solid substrate with nanoscale structures of inverted triangular grooves is investigated by using molecular dynamics simulation method under the parameter space spanned by structure geometry and solid-liquid molecular interaction potential strength. Three wettability states, namely Cassie nonwetting state, Cassie-to-Wenzel transition state and Wenzel wetting state, are identified with various geometries and potential strength. For Cassie nonwetting state, increasing height of the triangles has less effect on wettability transition with weak solid-liquid molecular interaction. Besides, the Cassie nonwetting state is less sensitive to different interval between the triangles as solid-liquid molecular interaction is weak. For Cassie-to-Wenzel transition state, increasing height of the triangles and decreasing interval between the triangles decrease wettability. For Wenzel wetting state, increasing interval between the triangles with low height increases wettability. With strong solid-liquid molecular interaction, different interval between the triangles results in wetting state transition from Wenzel to transition state. What’s more, liquid droplet changes its state from Wenzel wetting state to Cassie-to-Wenzel transition state with increasing height of the triangles or decreasing interval between the triangles. Three wettability transition regions are identified in the parameter space.