Attractive Point Research Articles

Iterative Likelihood: A Unified Inference Tool

We propose a framework for inference based on an “iterative likelihood function,” which provides a unified representation for a number of iterative approaches, including the EM algorithm and the generalized estimating equations (GEEs). The parameters are decoupled to facilitate construction of the inference vehicle, to simplify computation, or to ensure robustness to model misspecification and then recoupled to retain their original interpretations. For simplicity, throughout the paper, we will refer to the log-likelihood as the “likelihood.” We define the global, local, and stationary estimates of an iterative likelihood and, correspondingly, the global, local, and stationary attraction points of the expected iterative likelihood. Asymptotic properties of the global, local, and stationary estimates are derived under certain assumptions. An iterative likelihood is usually constructed such that the true value of the parameter is a point of attraction of the expected log-likelihood. Often, one can only verify that the true value of the parameter is a local or stationary attraction, but not a global attraction. We show that when the true value of the parameter is a global attraction, any global estimate is consistent and asymptotically normal; when the true value is a local or stationary attraction, there exists a local or stationary estimate that is consistent and asymptotically normal, with a probability tending to 1. The behavior of the estimates under a misspecified model is also discussed. Our methodology is illustrated with three examples: (i) estimation of the treatment group difference in the level of censored HIV RNA viral load from an AIDS clinical trial; (ii) analysis of the relationship between forced expiratory volume and height in girls from a longitudinal pulmonary function study; and (iii) investigation of the impact of smoking on lung cancer in the presence of DNA adducts. Two additional examples are in the supplementary materials, GEEs with missing covariates and an unweighted estimator for big data with subsampling. Supplementary files for this article are available online.

Spontaneous Directional Self‐Cleaning on the Feathers of the Aquatic Bird Anser cygnoides domesticus Induced by a Transient Superhydrophilicity

AbstractIn nature, the feathers of the goose Anser cygnoides domesticus stay superhydrophobic over a long term, thought as the main reason for keeping the surface clean. However, contaminants, especially those that are oleophilic or trapped within textures, cannot be removed off the superhydrophobic feathers spontaneously. Here, a different self‐cleaning strategy based on superhydrophilic feathers is revealed that is imparted by self‐coating of the amphiphilic saliva, which enables removing away low‐surface‐tension and/or small‐size contaminants by forming directional water sheeting depending on their unique anisotropic microstructures. Particularly, the surface superhydrophilicity is switchable to superhydrophobicity upon exposure to air for maintaining a clean surface for a long time, which is further enhanced by coating with self‐secreted preening oil. By alternate switching between a transient superhydrophilicity and a long‐term stable superhydrophobicity, the goose feathers exhibit an integrated smart self‐cleaning strategy, which is also shared by other aquatic birds. An attractive point is the re‐entrant structure of the feathers, which facilitates not only liquid spreading on superhydrophilic feathers, but also long‐term stability of the cleaned surface by shedding water droplets off the superhydrophobicity feathers. Thus, artificial self‐cleaning microtextures are developed. The result renews the common knowledge on the self‐cleaning of aquatic bird feathers, offering inspiration for developing bioinspired self‐cleaning microtextures and coatings.

Roll-to-roll fabrication of highly transparent Ca:Ag top-electrode towards flexible large-area OLED lighting application

Transparency and bendability are some of the most attractive unique selling points for organic light-emitting diode (OLED) lighting, enabling a variety of new application possibilities for industrial and private end-users. The roll-to-roll (R2R) OLED fabrication based on thermal evaporation offers a fast, continuous-running solution for producing flexible OLEDs at a lower cost. In this work, R2R fabricated large-area highly transparent thermal co-evaporated Ca:Ag (2:1 vol.%) top-electrode with mean transmittance of 64% over the visible range and a corresponding sheet resistance of as low as 21 Ω sq−1 was achieved. By increasing the film thickness to 24 nm, the sheet resistance can be further reduced to 12 Ω sq−1, albeit with a lower mean transmittance of 58%. The Ca:Ag electrode demonstrates a high mechanical durability through 1000 bending cycles, which is highly desirable as a characteristic for flexible electronics, as well as for the R2R fabrication. Finally, the stability of the Ca:Ag electrode in vacuum and ambient was studied as well.

Natural products as pharmacological modulators of mitochondrial dysfunctions for the treatments of Alzheimer's disease: A comprehensive review.

Alzheimer's disease (AD) is the most common progressive neurodegenerative disorder characterized by neuronal loss and cognitive impairment that harshly affect the elderly individuals. Currently, the available anti-AD pharmacological approaches are purely symptomatic to alleviate AD symptoms, and the curative effects of novel anti-AD drugs focused on Aβ target are disappointing. Hence, there is a tremendous need to adjust AD therapeutic targets and discover novel anti-AD agents. In AD, mitochondrial dysfunction gradually triggers neuronal death from different aspects and worsens the occurrence and progress of AD. Consequently, it has been proposed that the intervention of impaired mitochondria represents an attractive breakthrough point for AD treatments. Due to chemical diversity, poly-pharmacological activities, few adverse effects and multiple targeting, natural products (NPs) have been identified as a valuable treasure for drug discovery and development. Multiple lines of studies have scientifically proven that NPs display ameliorative benefits in AD treatment in relation to mitochondrial dysfunction. This review surveys the complicated implications for mitochondrial dysregulation and AD, and then summarizes the potentials of NPs and their underlying molecular mechanisms against AD via reducing or improving mitochondrial dysfunction. It is expected that this work may open the window to speed up the development of innovative anti-AD drugs originated from NPs and improve upcoming AD therapeutics.

Airbus Active Debris Removal Service

With the increasing number of both functional and defunct space assets being present in orbit, and having a better understanding of the space environment, it is clear that there is a need for active debris removal (ADR) today if not in the very near future. Previous demonstrators have been successful such as the RemoveDEBRIS mission which was co-funded by the European Commission and produced by a set of partners. Airbus have also worked extensively on other projects to develop the capability to rendezvous and capture objects in space (such as the ATV with 5 successful flights, e-Deorbit, DEOS, and Space Tug). Airbus have been working with agencies and industry to create a removal service with the aim of being both technically feasible and at an attractive price point to potential customers. The capture solutions have been outlined and an example mission profile is shown for providing the service for a mega-constellation operator. With this setup, a total of 20+ spacecraft could be deorbited with a single ADR vehicle which would provide an affordable price point.

Decenter Error Sensing Technology of Sparse Aperture Telescope Systems

The imaging quality of sparse aperture telescope systems is degraded by several factors including design, manufacturing, and arrangement errors. To achieve a high-resolution, the optical system requires an accurate control of not only the wave-front errors such as the piston and tip-tilt but also the decenter errors. Decenter diminishes the field of view of synthetic systems heavily and causes frequency shifting as well. In this paper, we firstly present an approach to sense the decenter of the sparse aperture telescope using the multi-beam interference method based on phase shift and centroid extraction algorithm. The most attractive point of our method is that it can sense not only the decenter but also the other wave-front errors simultaneously, but does not need to install any additional sensors. The numerical simulations are described and preliminary experiments are performed for validation, demonstrating that this technique is efficient and accurate and could be used to guide future sparse aperture telescope error correction.

On the Throughput Optimization in Large-Scale Batch-Processing Systems

We analyze a data-processing system with n clients producing jobs which are processed in batches by m parallel servers; the system throughput critically depends on the batch size and a corresponding sub-additive speedup function that arises due to overhead amortization. In practice, throughput optimization relies on numerical searches for the optimal batch size which is computationally cumbersome. In this paper, we model this system in terms of a closed queueing network assuming certain forms of service speedup; a standard Markovian analysis yields the optimal throughput in w n4 time. Our main contribution is a mean-field model that has a unique, globally attractive stationary point, derivable in closed form. This point characterizes the asymptotic throughput as a function of the batch size that can be calculated in O(1) time. Numerical settings from a large commercial system reveal that this asymptotic optimum is accurate in practical finite regimes.

Testing methods to increase consumption of healthy foods evidence from a school-based field experiment in Viet Nam

Schools are an attractive entry point to improve children’s diets, as their eating habits can be shaped during childhood and the information disseminated from school can reach adults through children. We implemented a cluster-randomized trial in 12 schools in peri-urban Viet Nam to assess if two school-based interventions increased knowledge of healthy diets among children and their parents, as well as children’s consumption of healthy foods. First, children were given lessons about food before school lunch and encouraged to share the lessons with their parents. Second, children were provided with healthy snacks to reinforce messages about healthy eating. We found that in the short term, the nutrition lessons raised the knowledge index score of the children by 0.35 standard deviation. After six months, this intervention lost its effectiveness, emphasizing the need for linkage between knowledge and practice. By itself, free access to fruit at school increased the children’s daily fruit consumption by half a portion, but not at the expense of home fruit consumption. Access to healthy foods at school can therefore be an effective measure to raise children’s healthy consumption. Child-parent communication was not a reliable channel for knowledge dissemination in our setting.

An Analytical Study to Evaluate the Safety of Reusing of the Vomited Leech in Leech Therapy

Background: Leech therapy is a point of attraction in the medical as well as in the scientific world due to its various outstanding properties, while studying the Ayurveda and scientific literature one can find difference, i.e., discarding after single use as per modern literature, but in Ayurveda, it can be reused after 7 days of leech therapy. Studies of such kind were not carried or published in any scientific journals, so ethical approval and developing scientific methods for validating the study were necessary, so a pilot study began with ethical clearance. Objective: The objective of the study was to evaluate the bacterial and fungal count of leech saliva and blood emesis before and after leech therapy using disc diffusion method. Materials and Methods: Leeches were collected from the normal habitat from Mangalore region possessing the same weight and morphological characteristics as that of the Nirvisha Jalouka as mentioned in classics (Shanku-mukhi). The selected leeches were stored in well water having nonchlorinated with minimum bacterial load. The well water was selected from three geographical regions of Belagavi city, and among them, one sample was selected having minimal bacterial load. Ten patients with infectious skin diseases who were indicated for Jalaukavacharana (Vidradhi, Dushta-vrana) were selected. The experimental leech saliva was tested for total bacterial count (TBC) and total fungal count (TFC) before and on 8th day of application, along with venous blood of the patient and blood vomitus of leech after application was tested for TBC and TFC. Statistical analysis was done based on TFC and TBC before and after application. Results: TBC and TFC of leech saliva at 8th day and before application were similar which indicates the leech gut has destroyed the bacteria or inhibited the growth of bacteria. Conclusion: TBC and TFC help to produce evidence that after application of leech and proper vomiting will not allow the growth of bacteria. Hence, safely, it can be reused after 7 days.

Role of vaccine science diplomacy in low-middle-income countries for eradicating the vaccine-preventable diseases: Targeting the "LAST MILE".

The meaning of “vaccine diplomacy (VD)” is defined as “the use of vaccines to increase a country's diplomatic relations and influence over other nations.” The golden era of vaccine science diplomacy started during the time of Cold War between the United States (US) and the Union of Soviet Socialist Republics (USSR) with the development of a prototype of oral polio vaccine by the US Scientist Dr Albert Sabin working along with his Soviet counterparts. The foundation stone was already laid down by Edward Jenner when he shared his technique of the smallpox vaccine with other major countries to curb the spread of smallpox. Eventually, such a step led to the eradication of such a deadly disease. Only time has changed, not the tide. Even today, vaccines continue to remain as one of the important tools for achieving Millennium Developmental Goals (MDGs) and other targets in developing countries like India. During the wake of the Corona Virus Diseases-19 (COVID-19) pandemic, India's role in developing its vaccine science diplomacy has been a point of attraction. The phase-3 trial of Covaxin being developed by Bharat Biotech started in Lucknow and Gorakhpur in October 2020, and it is widely considered as the forerunner for the Indian vaccine market. As per the Union Health Ministry of India- “The Union Government is working on at least five distinct ways, ranging from free vaccines to guaranteed supply, in which it can help its immediate neighbours and countries in West Asia, Africa and even Latin America—officials familiar with the plan said on conditions of anonymity. The idea is to leverage the country's standing as the world's vaccine factory to merge diplomatic ties. Historically, it is observed that by the development and introduction of newer vaccines from time to time, many dismaying hurdles to vaccine science diplomacy (VSD) arise from ongoing wars and political instability. The current scenario is that both VSD and VD are at crossroads, and there is a possibility of getting a good direction if we make a piggyback policy approach of vaccine diplomacy along with the foreign policy. The lessons learned from the past must be followed now and, in the future, to make a better world for all. We acknowledge that the COVID-19 episode has again highlighted the dire need for VSD, and we assume that not only COVID-19 but in future, emerging and re-emerging diseases will occur so we have to prepare ourselves for combatting those future emerging and re-emerging diseases.

Can playing Spirograph lead to an ordered structure in self-propelled particles?

Understanding the local dynamics of microorganisms infecting a cell could help us develop efficient strategies to counter their aggregation. In the present study we have introduced a simple model of self-propelled particles (SPPs) with constant linear velocity, both in 2 and 3 dimensions, which captures the essential features of a microorganism's aggregation as well the dynamics around an attractive point (AP). The static behavior shows the presence of an icosahedral structure for a finite number of SPPs, and a hexagonal closed packed structure for an infinite number of SPPs, which was confirmed using Steinhardt bond order parameters for a 3-dimensional model. For a single SPP the dynamic behaviour involves the formation of orbits around the AP, which can be categorised into three dynamical regions based on the strength of coupling between the AP and SPP. For weak coupling we observe a rosette-like trajectory reminiscent of the pattern formed by the Spirograph toy. For intermediate coupling, circular trajectories were observed, and for very strong coupling the SPP was static and was always aligned with the AP. The radial distance from the AP to SPP was determined by the angular velocities of the SPP for the rosette-like region whereas for the circular and static regions, it was determined by the coupling constant. Even for a finite number of SPPs we observed the same behavior as long as the SPPs could rotate around the AP without colliding with each other.

Synthesis of substituted 3,4-dihydroquinazolinones via a metal free Leuckart-Wallach type reaction.

The 3,4-dihydroquinazolinone (DHQ) moiety is a highly valued scaffold in medicinal chemistry due to the vast number of biologically-active compounds based on this core structure. Current synthetic methods to access these compounds are limited in terms of diversity and flexibility and often require the use of toxic reagents or expensive transition-metal catalysts. Herein, we describe the discovery and development of a novel cascade cyclization/Leuckart–Wallach type strategy to prepare substituted DHQs in a modular and efficient process using readily-available starting materials. Notably, the reaction requires only the addition of formic acid or acetic acid/formic acid and produces H2O, CO2 and methanol as the sole reaction byproducts. Overall, the reaction provides an attractive entry point into this important class of compounds and could even be extended to isotopic labelling via the site-selective incorporation of a deuterium atom.

Current Research Trends and Perspectives on Solid-State Nanomaterials in Hydrogen Storage.

Hydrogen energy, with environment amicable, renewable, efficiency, and cost-effective advantages, is the future mainstream substitution of fossil-based fuel. However, the extremely low volumetric density gives rise to the main challenge in hydrogen storage, and therefore, exploring effective storage techniques is key hurdles that need to be crossed to accomplish the sustainable hydrogen economy. Hydrogen physically or chemically stored into nanomaterials in the solid-state is a desirable prospect for effective large-scale hydrogen storage, which has exhibited great potentials for applications in both reversible onboard storage and regenerable off-board storage applications. Its attractive points include safe, compact, light, reversibility, and efficiently produce sufficient pure hydrogen fuel under the mild condition. This review comprehensively gathers the state-of-art solid-state hydrogen storage technologies using nanostructured materials, involving nanoporous carbon materials, metal-organic frameworks, covalent organic frameworks, porous aromatic frameworks, nanoporous organic polymers, and nanoscale hydrides. It describes significant advances achieved so far, and main barriers need to be surmounted to approach practical applications, as well as offers a perspective for sustainable energy research.

The Discovery of the Great Wall of Jordan, Southern Levant

Great wall of Jordan also known as Khatt Shebib is a unique ancient wall situated in Southern Jordan near Maan City. The remains of the wall which includes towers, barracks, rooms …etc. are 150 km long from south to north, making it the longest linear archaeological site in southern Levant &in Jordan. The archaeological remains of the wall were first identified by British experts, the discovery was unveiled in 1948, then it was documented by air photographing in 1982, the Department of Antiquities explored it in 1992, with survey, excavations, & documentation continued to the present day. Located in the south of the Kingdom, the wall is the world's second longest after the China Wall, as it spans a distance of approximately 150 kilometers approximately, making it the region’s longest structure. Known locally as Hableh or Khatt Shebib, the wall stretches northwards from Ras Al Naqab in Maan Governorate extending to the Wadi Al Hasa area of Tafileh Governorate, A Jordanian team of archaeologists and experts imitated a field project in 1992-1996, and 2020in order to document the nearby remains of the wall, where comprehensive survey and excavations urgently needed in several significant sites along the wall sides. The field study concluded in revealing significant architectural structures built directly adjacent to the wall, also focused on the importance of the wall to be an attractive point for tourism in South Jordan. The date of the wall's construction clearly refers to Nabataean Period.

Perceived Safety and Security Concerns among Tourists in Thamel-A Tourism Hub in Kathmandu Valley, Nepal

The safety and security of a destination is an essential factor that helps travelers decide whether to visit or not. In Nepal, Thamel is the main destination for tourists due to the availability of multiple facilities and services. In fact, most of the tourists who use airspace to travel to Nepal, start and conclude their journey in Thamel. Therefore, the safety and security of Thamel is an important factor that influences the fate of the Nepalese tourism industry. However, there is a lack of research to understand the safety and security situation of Thamel. The purpose of this exploratory study is to assess the overall security situation and challenges in Thamel. Descriptive statistics are used to present the findings. Findings suggest that Thamel as a tourism destination has many areas for improvement to provide better tourist experiences. Since Thamel is a starting and concluding point of attraction for tourists, we offer important managerial implications and future research directions.

NEW EU STRATEGY FOR CENTRAL ASIA: HISTORY, VISION, PROSPECTS

Today, the Central Asian region is once again becoming a point of attraction for the interests of the international community—in geopolitical, as well as in trade and economic terms. The interests of major world powers intersect here, and each has its own approach to establishing relations with the regional countries. The European Union, which never considered this region a geopolitical priority, has been implementing its own Central Asia Strategy since 2007. In July 2017, the Council of the European Union decided to completely revise the Strategy based on new realities, as well as the ambitions and priorities of the regional states in their relations with the EU. A new strategy for relations between the European Union and Central Asia was adopted in June 2019. The revision of the strategy is slated to allow the EU to strengthen its cooperation with the Central Asian countries, highlight the most effective projects, and revise those aspects of interaction that did not bring the desired results. Currently, there is an intensification of intra-regional cooperation in Central Asia; there are positive trends in the development of dialog on important issues of the regional agenda. For this reason, the approaches and tools of European diplomacy in the implementation of its policy in Central Asia are expected to undergo significant adjustments as the Strategy is updated. The subject of this article is precisely this transit period in the relations between the European Union and Central Asia.

CONCEPTUAL STUDY OF CORONA VIRUS DISEASE (COVID-19) IN RELATION WITH SANNIPATIK JWARA: AN AYURVEDIC PERSPECTIVE

In recent period of time Novel Corona virus has become the center point of attraction, due to it pandemic effect on the entire world. This pandemic disease has taken about a million of life and still its outbreak is continued. News reports have been addressing its origin in China by consumption of bats which were af-fected by Novel Corona virus (SARS-CoV2). Its spread in the entire world was a shock and the actual fact was unrevealed. Human beings live in an environment which is filled with various bacteria, fungus, virus and different types of animals since early life. But how this new bacteria or viruses get erupted, it is noth-ing but the effect of rapid modernization and urbanization. Since modernization and change in lifestyle of an individual is related to increase in demand of products which has forced the bar towards artificial world. Nature has been deteriorated for fulfilling the needs but still it is insufficient and in result natural energy /immunity is replaced by artificial. So human beings are more depended on artificial antibodies to safe-guard themselves when they are attacked by different viruses or bacteria. China is a classic example of ar-tificial food production and consumption state, so their people immunity is severely hampered, that result in the outbreak of virus. Similarly, this virus is affecting the entire world but still we have measures to fight this disease is by raising our immunity power. This can be done properly when we understand the disease in a better manner. Ayurveda is the natural science, which helps us to understand the disease and the measure to increase immunity accordingly.

Attractive point and nonlinear ergodic theorems without convexity in reflexive Banach spaces

In this paper, we prove attractive point theorem for two commutative generic 2-generalized Bregman nonspreading mappings in reflexive Banach spaces. Also, a nonlinear ergodic theorem of Baillon type without convexity assumption on the aforementioned mappings is proved in the space. Our results improve and generalize many results announced recently in the literature.

Evolution of Novartis' Small Molecule Screening Deck Design.

This article summarizes the evolution of the screening deck at the Novartis Institutes for BioMedical Research (NIBR). Historically, the screening deck was an assembly of all available compounds. In 2015, we designed a first deck to facilitate access to diverse subsets with optimized properties. We allocated the compounds as plated subsets on a 2D grid with property based ranking in one dimension and increasing structural redundancy in the other. The learnings from the 2015 screening deck were applied to the design of a next generation in 2019. We found that using traditional leadlikeness criteria (mainly MW, clogP) reduces the hit rates of attractive chemical starting points in subset screening. Consequently, the 2019 deck relies on solubility and permeability to select preferred compounds. The 2019 design also uses NIBR's experimental assay data and inferred biological activity profiles in addition to structural diversity to define redundancy across the compound sets.

A Framework with Enhanced Security for Service Oriented Architecture

Background: Service Oriented Architecture is one of the acceptable frameworks for application development which provides better functionality such as composability, reliability, reusability, distributed deployment and interoperability which meet enterprises dynamics. So, SOA framework is a point of attraction for consumers. Objective: However, SOA framework fails to provide security at a granular level. Along with SOA functionality, the consumer also needs a secure environment so that each application can be reliable. Methods: SOA functionality like modularity and reusability are helpful in cross-organization context but these quality requirements reduce the security of the applications. In the past years, many security techniques have been provided by different researchers, still, security is a concern of SOA framework. Results: Most of the research focus security enhancement at higher layers of SOA reference architecture only so that SOA functionality remains unaffected. In this paper, the author(s) provided a framework which enhances the security at both the higher layer and lower layer. Conclusion: Also, this framework focuses on security enhancement at the granular level so that application-level security can be enhanced. The author(s) also included a technique to keep SLA similar to the exiting application after the implementation of security at each layer. This framework will be helpful in enhancing the end to end security and reliability of an application.