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As wireless communication technology continues to advance, the number of intelligent devices, such as computers, mobile phones, and iPads, is increasing rapidly. To keep up with the growing demand for data and improved network efficiency, additional base stations (BSs) are deployed, and bandwidth allocation is being increased in the sixth-generation (6G) wireless network. While these improvements have enhanced the physical layer of wireless communication, deploying excessive BSs can be costly and may lead to issues such as backhaul congestion and decreased performance. Additionally, frequent and asynchronous access to popular information generates a significant amount of duplicate data, thereby wasting energy and processing resources. Therefore, we use content caching, which involves storing content at the network's edge, such as at BSs or terminal devices. This allows the direct delivery of content to requesters, eliminating the need for backhaul or core network transmission. In this survey paper, we examine state-of-the-art content caching techniques that are specifically designed for mobile edge computing environments. The article classifies the existing content caching scheme into various categories based on a set of parameters, including caching techniques, criteria, location, objective functions, and supporting algorithms. Furthermore, a comprehensive analysis is conducted to investigate the critical aspects of existing schemes. Finally, the study identifies and discusses open research issues and challenges that necessitate further research to enhance content caching schemes. [ABSTRACT FROM AUTHOR]

We describe the AMBITION project, a mission to return the first-ever cryogenically-stored sample of a cometary nucleus, that has been proposed for the ESA Science Programme Voyage 2050. Comets are the leftover building blocks of giant planet cores and other planetary bodies, and fingerprints of Solar System's formation processes. We summarise some of the most important questions still open in cometary science and Solar System formation after the successful Rosetta mission. We show that many of these scientific questions require sample analysis using techniques that are only possible in laboratories on Earth. We summarize measurements, instrumentation and mission scenarios that can address these questions. We emphasize the need for returning a sample collected at depth or, still more challenging, at cryogenic temperatures while preserving the stratigraphy of the comet nucleus surface layers. We provide requirements for the next generation of landers, for cryogenic sample acquisition and storage during the return to Earth. Rendezvous missions to the main belt comets and Centaurs, expanding our knowledge by exploring new classes of comets, are also discussed. The AMBITION project is discussed in the international context of comet and asteroid space exploration. [ABSTRACT FROM AUTHOR]

Enforcing network slice isolation in 5G Radio Access Networks (RANs) can degrade a network slicing solution’s ability to efficiently support different types of traffic. In addition, competing virtual network operators may share one network infrastructure that forces network slicing solutions to provide fair treatment between them. This work presents Flexible Priority Scheduling (FPS). This RAN network slicing solution provides isolated treatment to slices with different traffic types, further exploring their needs and flexibility to achieve a more efficient solution. It does so by defining a contract interface that allows a flexible representation of different types of traffic, from heavy throughput services to low latency and bursty traffic. Furthermore, the presented contract representation allows a fair treatment of the tenant’s traffic in the Medium Access Control (MAC) scheduler that enforces this slicing solution: Priority Adaptation Slice Scheduler (PASS). [ABSTRACT FROM AUTHOR]

The solid-phase exchange of ethanol in γ-cyclodextrin inclusion compounds has afforded binding of volatile organic compounds not forming inclusion compounds with dry γ-cyclodextrin or its hydrates. The obtained results can be used in the development of efficient filters to remove aromatic compounds from air. [ABSTRACT FROM AUTHOR]

Examines the life cycle of Suidasia medanensis and Suidasia pontifica under laboratory conditions. Range of relative humidity; Average number of days required for the eggs to develop into adults; Mean longevity of mated females and males.

The Main Belt Comet 133P/Elst-Pizarro is one of the targets in China's asteroid exploration mission. To support this goal, gravity field estimation for this celestial object was simulated and analyzed using two-way and four-way range rate observations. A circular terminator orbit was designed for the spacecraft, and the forces acting on it were modeled to estimate the related dynamic values. Various solutions using different tracking modes and different orbital distances were approximated using the least squares method, constrained by the currently known GM bounds of this comet. The simulation results showed that unlike the two-way range rate observables, the four-way range rate observables are found to be able to reduce the correlations between the gravity field coefficients therefore decrease their uncertainties, especially in lower degrees. [ABSTRACT FROM AUTHOR]

One of the primary goals of Hayabusa2 is to land on the asteroid Ryugu to collect its surface materials. The key for a successful touchdown is to find a promising landing site that meets both scientific and engineering requirements. Due to the limited availability of pre-arrival information about Ryugu, the landing site selection (LSS) must be conducted based on proximity observations over a limited length of time. In addition, Ryugu was discovered to possess an unexpectedly high abundance of boulders with an absence of wide and flat areas, further complicating the LSS. To resolve these problems, we developed a systematic and stepwise LSS process with a focus on the surface topography of Ryugu and the associated touchdown safety. The proposed LSS scheme consists of two phases: Phase-I LSS, a comprehensive survey of potential landing areas at the 100-m scale based on the global mapping of Ryugu, and Phase-II LSS, a narrowing-down process of the candidate landing sites at the 10-m scale using high-resolution images and a local terrain model. To verify the feasibility of a precision landing at the target site, we also investigated the landing dispersion via a Monte Carlo simulation, which incorporates the effect of the irregular surface gravity field. One of the major characteristics of the Hayabusa2 LSS developed in this study is the iterative feedback between LSS analyses on the ground and actual spacecraft operations near the target asteroid. Using the newly developed method, we chose a landing site with a radius of 3 m, and Hayabusa2 successfully conducted its first touchdown on February 21, 2019. This paper reports the methodology and results of the stepwise iterative LSS for the first Hayabusa2 touchdown. The touchdown operation results reconstructed from flight data are also provided, demonstrating the validity of the adopted LSS strategy. [ABSTRACT FROM AUTHOR]

We analyzed the BVR photometry of the comets 63P/Wild 1 and C/2012 K1 (PANSTARRS) obtained between March 2013 and May 2014, with 0.20-m to 2.0-m aperture telescopes installed in Australia, Europa and USA. We have found R-band nuclear magnitudes H 0 = 16.3 ± 0.6 and 12.52 ± 0.02 for 63P and K1 comets. Admitting a geometric albedo equal to 0.04, the nuclei have a radius equal to 1.5 ± 0.4 and 8.67 ± 0.08 km respectively. Using the Lomb-Scargle periodogram, we found that the most probable periods of rotation of these nuclei are 14 ± 2 h and 9.4 ± 0.4 h, with a peak-to-peak light curve amplitude of 0.85 ± 0.01 and 0.4 ± 0.2 magnitudes. The inner coma of both comets were probably optically thin and in steady-state during all duration of our observations seasons. The average normalized reflectivity gradient S' of the coma of 63P and K1 are 10 ± 15 (1 σ ) and 8 ± 7 %/100 nm in the spectral range between 440 and 647 nm, which have indicated that both comets are statistically redder than the Sun. The Kruskal–Wallis H-test suggests that the distribution of the color indexes B-V, V-R, and B-R of the objects are similar, indicating some kind of equality between the physical or mineralogical properties of the comas of these comets. [ABSTRACT FROM AUTHOR]

Ecological observations were made on house dust mites of Kolkata as they form a major part of synanthropic mite community. Dust samples were collected with regard to the abundance of mite in relation to certain socio-ecological parameters like, habitat preference, location of house, construction pattern of house, types of mattresses used and the frequency of cleaning of mattresses. Among two different habitats examined, bed dust contained significantly higher mite population ( p < 0.01) than the corresponding bedroom floor dust. The density of total mites and glycyphagids are significantly higher in rural houses in comparison to those of urban houses. In contrast, rural houses contained least number of pyroglyphids/g of dust. The density of total mites as well as pyroglyphid mites/g of dust are higher in mud house in comparison to concrete house. The density of total mites, pyroglyphids and glycyphagids are higher in cotton mattress in comparison to that of foam mattress. The frequency of cleaning has a significant effect on reducing mite densities i.e., the more the frequency of cleaning the lesser are the mite densities. [ABSTRACT FROM AUTHOR]

In order to unravel the relation of the nanostructure of Cr:YAlO (Cr:YAG) crystal fibers controlled by the laser-heated pedestal growth (LHPG) technique with different growth conditions, the nanostructural analysis of Cr:YAG crystal fiber was investigated by high-resolution transmission electron microscopy (HRTEM), which offers nano-scale information in the core region and inner/outer cladding interface and the mechanism of inter-diffusion process during growth. HRTEM analysis indicates that the core has high crystallinity and a sharp core/inner-cladding interface. γ-AlO nanocrystals were formed during YAG/SiO inter-diffusion. To further enhance the Cr concentration in YAG crystal fiber, the Cr ions were replenished using an electron gun to deposit CrO and divalent-ion oxide (CaO or MgO) on the source rod circumference before LHPG. It was observed that Ca diffuses into the source rod more efficiently than Mg, while generating fewer defects and stacking faults. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases are the leading cause of death worldwide; they are mainly due to vascular obstructions which, in turn, are mainly caused by thrombi and atherosclerotic plaques. Although a variety of removal strategies has been developed for the considered obstructions, none of them is free from limitations and conclusive. The present paper analyzes the physical mechanisms underlying state-of-art removal strategies and classifies them into chemical, mechanical, laser and hybrid (namely chemo-mechanical and mechano-chemical) approaches, while also reviewing corresponding commercial/research tools/devices and procedures. Furthermore, challenges and opportunities for interventional micro/nanodevices are highlighted. In this spirit, the present review should support engineers, researchers active in the micro/nanotechnology field, as well as medical doctors in the development of innovative biomedical solutions for treating vascular obstructions. Data were collected by using the ISI Web of Knowledge portal, buyer's guides and FDA databases; devices not reported on scientific publications, as well as commercial devices no more for sale were discarded. Nearly 70% of the references were published since 2006, 55% since 2008; these percentages respectively raise to 85% and 65% as regards the section specifically reviewing state-of-art removal tools/devices and procedures. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the level of comfort among nursing students during sexual counseling to patients who have chronic medical conditions. The sample of this descriptive study consisted of 161 students who study at the third and fourth years at a health college. More than half of the students reported being comfortable or a slightly comfortable during providing sexual counseling to patients who have chronic conditions. Students who are not comfortable with answering questions related to sexuality ( p = 0.000), find initiating a conversation on future sexual problems with the patient is inappropriate unless the patient brings it up ( p = 0.007), and nurses should not talk about sexual issues in a routine way with patients ( p = 0.026) who do not feel comfortable during sexual counseling. In order to provide nursing students feeling comfortable, the issue of sexual counseling to patients who have chronic conditions should take place during the nursing education. [ABSTRACT FROM AUTHOR]

Female sexual dysfunctions are common in the general population and remain a multifaceted problem that continues to be under recognized and under treated. This article reports a descriptive analytic study to assess prevalence of female sexual dysfunction and related factors for under treatment. In this cross sectional study, 1054 married women age 18–59 years were randomly selected from rural and urban health centers of Bushehr province. Data was collected by a questionnaire for demographic characteristic and Female Sexual Function Index for assessment of sexual dysfunction. For data analysis descriptive analytic tests were used. A total of 71.1% of subjects reported desire disorder. Prevalence of arousal, lubricating, orgasmic and pain disorders were 66.4, 38, 34.8 and 38.4%, respectively. Desire and arousal disorder were significantly interrelated with age, educational level, economic and marital status, smoking behavior of subjects and age, educational level, occupation and marital status of their husbands. Lubricating disorder was interrelated with age, educational level, occupation, smoking behavior and economic status of subjects and age, educational level, occupation of their husbands. Orgasmic disorder was significantly interrelated with age, educational level, occupation, economic status and smoking behavior of subjects and age, educational level and occupation of their husbands. There was a significant relationship between pain disorder with age, smoking, economic status of subjects and age, educational level and occupation of their husbands. 47.1 percent of subjects agreed that they had a problem. Only 9.2% of them reported going for treatment. Most of participants reported that they were ashamed of talking about these problems. Female sexual dysfunction is prevalent in Bushehr province but treatment rate is very low. Screening for sexual disorder, initiating dialogue by professionals and establishing a counseling plan may provide the opportunity to improve their sexual health. [ABSTRACT FROM AUTHOR]

Spectral characteristics and kinetic processes of the laser-induced plasma used for the growth of films from titanium oxides were investigated. The experiments were carried out in vacuum, oxygen, and an oxygen radiofrequency discharge plasma and its afterglow. A collision-radiative model describing the state-to-state kinetics of titanium atoms and ions at various stages of flight of laser-induced plasma was proposed. It was shown that the conditions of local thermodynamic equilibrium are disturbed because of a fast gas-dynamic expansion of plasma. Nonetheless, the distribution functions of titanium atoms and ions over excited states are described by the Boltzmann formulas with different temperatures. [ABSTRACT FROM AUTHOR]

This article reviews theoretical perspectives about the development of ethnic Chinese-owned enterprises in two major sets of literature. The first school is one that adopts culture as the primary explanatory tool for the dynamism of Chinese enterprise. The second school employs the concept of transnationalism, which has served to create a link between identity and capitalism, to analyse Chinese entrepreneurship. Both sets of literature argue that common ethnic identity facilitates the creation of business networks, which explains the rise of ‘Chinese capitalism’. This study questions the foundations of these theoretical arguments by tracing the evolution of family firms and by employing the concept of ‘generational change’. [ABSTRACT FROM AUTHOR]

Allergy to house dust mites, particularly tothe genus Dermatophagoides is a fairlycommon problem in Calcutta and its adjoiningareas since last two decades. Both the commonspecies of the genus Dermatophagoidesi.e. D. farinae and D.pteronyssinus are found to be abundant in thedust samples collected from beds of patientssuffering from nasobronchial allergic disordes.The presence of these mites in quite a goodnumber in the patients' beds are clinicallycorrelated with the aetiopathology of variousallergic manifestations like bronchial asthma. Dermatophagoides mites may occupydifferent niches in the homes of asthmatics andare more common in beds than elsewhere in thehouse, however, the distribution and abundanceof these mites are influenced by somesocio-ecological factors. The aim and objectiveof the present study is to assess the impact ofsome common socio-ecological managementpractices like the age of house, age ofmattress, type of mattress, frequency ofcleaning of the mattress and even the economicstatus of the patients on the growth,multiplication and finally accumulation ofthese mites in the patients' surroundings.Proper identification of offending allergensand subsequent reduction of load of these miteallergens from the patient's environment may behelpful for the prophylactic management ofthese diseases in Calcutta metropolis. [ABSTRACT FROM AUTHOR]

Examines the virus-pesticide interactions in Ixodes persulcatus and Amblyomma hebraeum ticks. Impact of pesticide on the survival of non-infected ticks; Influence of virus on non-infected ticks.

Hayabusa2 is the ongoing JAXA's sample and return mission to the asteroid Ryugu. In late 2018, Ryugu was in superior solar conjunction with the Earth. It is the first time that a spacecraft experiences the blackouts in the communication link with the Earth while hovering around a small celestial body. In this article, the design of the nominal conjunction trajectory flown by the Hayabusa2's spacecraft is presented. The requirements for the conjunction trajectory were (1) to guarantee a low fuel consumption, (2) to ensure the visibility of the asteroid by the spacecraft's wide angle camera ( 60 ∘ FoV), and (3) to increase the spacecraft altitude to a safety location (∼ 109 km ) from the nominal BOX-A operation of 20 km (Home Position - HP). Finally, (4) to return at BOX-A after the conjunction phase. Given the mission constraints, the designed conjunction trajectory appears to have a fish-shape in the Hill coordinates therefore we renamed it as "ayu" (sweetfish in Japanese) trajectory. The optNEAR tool was developed for the guidance (Δ V s planning) and navigation design of the Hayabusa2's conjunction mission phase. A preliminary sensitivity analysis in the Hill reference frame proved that the ayu trajectory is a good candidate for the conjunction operation of hovering satellite. The solution in the Hill coordinates is refined in the full-body planetary dynamics (optNEAR Tool) before flight. The ayu conjunction trajectory requires (a) two deterministic Δ V s at the Conjunction Orbit Insertion (COI) point and at the Home-position Recovery Maneuver (HRM) point respectively. (b) Two stochastic Δ V s , known as Trajectory Correction Manoeuvres (TCMs), before and after the deep conjunction phase are also required. The constraint linear covariance analysis in the full-body dynamics is here derived and used for the preliminary guidance and navigation planning. The results of the covariance analysis were validated in a nonlinear sense with a Monte Carlo approach which proved the validity of the semi-analytic method for the stochastic Δ V s planning derived in this paper. [ABSTRACT FROM AUTHOR]