bluuebunny/crossref_metadata_2025 huggingface dataset:
Research progress in non-classical microwave states preparation based on cavity optomechanical system
Authors: Luo Jun-Wen , Wu De-Wei , Miao Qiang , Wei Tian-Li ,   Information and Navigation College, Air Force Engineering University, Xi’an 710077, China
Published: December 2020

As a novel hybrid quantum system, cavity optomechanical system shows super strong coupling strength, extremely low noise level and considerable coherent time under superconducting condition. In this paper, we briefly introduce basic principles of cavity optomechanics and cavity optomechanical systems. Meanwhile, we also classify the widely studied cavity optomechanical systems as five categories in their materials and structures. Significant parameters of these optomechanical systems, such as quality factor, mass and vibrating frequency of mechanical oscillator, are listed in detail. Technical merits and defects of these optomechanical systems are summarized. Furthermore, we introduce the research progress of non-classical microwave quantum states preparation by utilizing generalized cavity optomechanical systems, and we also analyze the performance advancements and remaining problems of this preparation method. In the end, we summarize the application cases at present and look forward to the potential application scenarios in the future. Our summary may be helpful for researchers who are focusing on quantum applications in sensing, radar, navigation, and communication in microwave domain.
Static measurement of absolute gravity in truck based on atomic gravimeter
Authors: Wu Bin , Zhou Yin , Cheng Bing , Zhu Dong , Wang Kai-Nan , Zhu Xin-Xin , Chen Pei-Jun , Weng Kan-Xing , Yang Qiu-Hai , Lin Jia-Hong , Zhang Kai-Jun , Wang He-Lin , Lin Qiang ,   Institute of Optics, College of Science, Zhejiang University of Technology, Hangzhou 310023, China
Published: December 2020

Currently, most of the experimental apparatuses of atomic gravimeters are complex in structure, large in size, and poor in environmental adaptability, so that they cannot be used to implement the absolute gravity measurement. Thus, the application areas of atomic gravimeter are greatly limited. In this paper, we integrate a system of absolute gravity measurement on a truck based on a compact homemade atomic gravimeter. This atomic gravimeter has a small size, light weight, low power consumption, and its accuracy is estimated as 10 μGal in the case of laboratory environment. This system consists of atomic gravimeter for gravity measurement, passive isolation platform for vibration suppression, posture platform for tilt adjustment, differential GPS for altitude measurement, UPS for power supply, air-conditioned truck for temperature control and transportation. At first, we estimate the performance of environmental adaptability for this measurement system on the truck, and it is found that this system can still work even at a high field temperature of 40 ℃ and a big tilt angle of 8° for the road. Besides, the experimental procedures of absolute gravity measurement and the methods of processing measured data are introduced. The Coriolis effect is analyzed and the dependence of measured gravity on the orientation of the truck has been measured. Finally, the repeated line measurements are performed on a flat field road. The accuracy of self-coincidence for absolute gravity measurement is evaluated to be 30 μGal and the difference in measured gravity among different locations is about 3080 μGal. Besides, we obtain the vertical gravity gradient of the earth by measuring the absolute gravity values at different altitude sites on a slope road, and the value is estimated to be －231(36) μGal/m. The presented results can provide the basic reference for the field absolute gravity survey.
Thermal characteristics of surface liquid crystal vertical cavity surface emitting laser arrays
Authors: Wang Zhi-Peng , Zhang Feng , Yang Jia-Wei , Li Peng-Tao , Guan Bao-Lu ,   Key Laboratory of Opto-electronics Technology, Ministry of education, Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
Published: December 2020

In recent years, with the increase of information processing capacity of optical networks and the continuous improvement of high-density optical communication technology, the requirements for the performance of light sources are also increased. High-quality VCSEL with beam polarization stability control plays an increasingly important role in the above fields. The combination of liquid crystal and vertical cavity surface emitting laser (VCSEL) array can realize wavelength tunability and precise polarization control. At the same time, the introduction of liquid crystal will also change the thermal characteristics of VCSEL array. In this paper, the structure of VCSEL array is designed and the experimental research on the thermal characteristics of VCSEL array is carried out. The effects of nematic liquid crystal layer on the thermal characteristics of VCSEL array are compared and analyzed. The experimental results show that the threshold current temperature change rate of 1 × 1, 2 × 2 and 3 × 3 surface liquid crystal VCSEL array can be reduced by 23.6% and the thermal resistance can be reduced by 26.75%. Moreover, the saturated optical power of VCSEL array can be improved to a different degree. Meanwhile, the liquid crystal layer can effectively increase the heat transverse conduction and reduce the optical hole. The temperature difference between the light outlet and the table makes the heat conduction time very short at a small distance between the light outlet and the table, which is more conducive to the uniform temperature distribution of the laser array. The experimental results show that the temperature difference between the light outlet and the surrounding is less than 0.5 ℃. To sum up, the introduction of liquid crystal layer into VCSEL array not only greatly accelerates the thermal diffusion of laser array unit, but also reduces the junction temperature of active region, improves the thermal characteristics of VCSELs laser array, and lays a good theoretical and experimental foundation for realizing the high beam quality single polarization wavelength controllable VCSEL laser array.
Adhesion and nanotribological properties of folded graphene prepared by mechanical exfoliation
Authors: Deng Jian-Feng , Li Hui-Qin , Yu Fan , Liang Qi ,   School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China,   Instrumental Analysis Center, Shanghai Jiao Tong University, Shanghai 200240, China
Published: December 2020

Atomic force microscope was used to study the adhesion of mechanical exfoliated graphene under two different atmosphere conditions, air and nitrogen. It was found that the adhesion under nitrogen was smaller. The adhesion of graphene edge was larger than that of the inner region. The relationship between the adhesion of folded graphene and the number of layers along with its frictional properties were investigated under nitrogen atmosphere. The results showed that the adhesion was independent of the number of folded graphene layers. The frictional properties of each area of the folded graphene were far beyond the SiO2 substrate. The friction coefficients of the single layer, the fold on single layer, the double layers and the fold on double layers regions were successively decreased, which were 0.049, 0.031, 0.023 and 0.021 respectively. The friction forces were successively decreased as well. The frictional property of the folded graphene was weaker than the unfolded graphene of same number of layers due to the weaker bonding force between the layers. When measuring the adhesion with a sharp tip or a ball tip, the measurement history of adhesion had little influence on subsequent adhesion. Studies on freshly folded graphene in the air showed that the friction force of the folded region was significantly higher than that of the unfolded region.
High precision calibration of spectral parameters of CO at 1567 nm based on wavelength modulation-direct absorption spectroscopy
Authors: Wang Zhen , Du Yan-Jun , Ding Yan-Jun , Peng Zhi-Min ,   State Key Laboratory of Power Systems, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China
Published: December 2020

 Direct absorption spectrum (DAS) can be used to measure the molecular absorptivity function and determine the spectral parameters of the gas by fitting the measured absorptivity function. Wavelength modulation-direct absorption spectroscopy (WM-DAS) is based on DAS and combines with the idea of harmonic analysis in wavelength modulation spectrum (WMS). The measurement accuracy of absorptivity function can be effectively improved by using Fourier transform. In this paper, the absorptivity function of CO R5–R11 near infrared weak absorption line at 1567 nm is accurately reproduced by using the WM-DAS method combined with long optical path gas absorption cell at room temperature and low pressure. The standard deviation of the fitting residual reaches 3 × 10–5, and then the spectral parameters such as collision broadening, Dicke narrowing and speed-dependent collision broadening coefficients are measured in high precision.

 These parameters are compared with the results from the high sensitivity continuous wave cavity ring down spectroscopy (CW-CRDS). The experimental results show that the signal-to-noise ratio of the absorptivity function measured by CW-CRDS is about 2.5 times that of the long-path WM-DAS, and the measured spectral parameters are highly consistent. The relative errors of the collision broadening coefficients obtained by using the Voigt profiles of the two methods are less than 1%. At the same time, the detection limit of CO at 1567 nm based on the WM-DAS method is about 80 ppb, and the corresponding absorption coefficient is 2 × 10–10 cm–1, which is slightly higher than that from the CW-CRDS method. However, the WM-DAS method has the advantages of fast measurement speed, simple system and low cost, and is expected to provide a new method of measuring the weak absorption lines.
Effect of source-drain conduction in single-event transient on nanoscaled bulk fin field effect transistor
Authors: Lu Chao , Chen Wei , Luo Yin-Hong , Ding Li-Li , Wang Xun , Zhao Wen , Guo Xiao-Qiang , Li Sai ,   Key Laboratory of Particle and Radiation Imaging of Ministry of Education, Department of Engineering Physics, Tsinghua University, Beijing 100084, China,   State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Northwest Institute of Nuclear Technology, Xi’an 710024, China,   National Space Science Center, Chinese Academy of Sciences, Beijing 101400, China
Published: December 2020

Fin field effect transistor (FinFET) is a most widely used structure when the field effect transistor is scaled down to 30 nm or less. And there are few studies on single-event transient of FinFET devices with gate length below 30 nm. The single-event-transient on FinFET with gate length below 30 nm is worth studying. The single-event-transient responses of bulk FinFETs with 30 nm, 40 nm, 60 nm and 100 nm gate length are examined by using the pulsed laser and technology computer-aided design (TCAD) simulation in this article. First, we use the pulsed laser to ionize the gate of the FinFET device and detect the transient drain current of the FinFET device. The experimental results show that there are obvious platforms for the transient drain current tails of FinFETs with different gate lengths, and the platform current increases as the gate length of FinFET becomes shorter. The charges collected in the platform of FinFET devices with gate lengths of 100, 60, 40, and 30 nm are 34%, 40%, 51%, and 65% of the total charge collected in transient drain current, respectively. Therefore, when the FinFET device with the gate length below 100 nm, the platform current will seriously affect the device performance. Second, we use TCAD to simulate the heavy ion single-event effect of FinFET device and study the generation mechanism of platform region in transient drain current. The TCAD simulation explains this mechanism. Laser or heavy ions ionize high concentration electron-hole pairs in the device. The holes are quickly collected and the high concentration electrons are left under the FinFET channel. High concentration electrons conduct source and drain, generating the source-to-drain current at the tail of the transient drain current. Moreover the source-drain conduction enhances the electrostatic potential below the FinFET channel and suppresses high-concentration electron diffusion, making source-to-drain current decrease slowly and form the platform. The transient drain current tail has a long duration and a large quantity of collected charges, which seriously affects FinFET performance. This is a problem that needs studying in the single-event effect of FinFET device. It is also a problem difficult to solve when the FinFET devices are applied to spacecraft. And the generation mechanism of the transient drain current plateau region of FinFET device can provide theoretical guidance for solving these problems.
Relativistic regional innovation index and novel business cycle
Authors: Fang Xue-Jin , Cui Jun-Ying , Hu Dan-Dan , Han Xiao-Pu ,   Alibaba Research Center for Complexity Sciences, Hangzhou Normal University, Hangzhou 311121, China
Published: December 2020

In this paper, we propose a new type of relativistic regional innovation index by using the international patent application data. Based on the super-linear relationship between regional innovation and economic development, the new index can eliminate the influence of economic development level on innovation capabilities, and can effectively achieve the comparison of innovation capabilities among economies at different economic development levels. This new index is quite simple, and points out a series of new findings that are sharply different from the traditional cognitive phenomena, e.g. the index shows that the technological innovation capabilities of mainland China are among the highest in the world in 1980s. Moreover, the use of this new index not only can efficiently explain the economic growth of countries in the world at a higher level, but also find that there is a novel 20-year business cycle in the correlation between the index and economic growth rate. These results show that the index, as a simple single indicator, can achieve a higher degree of explanatory ability with minimal data dependence. This new index not only repositions the innovation capacity of world’s economies, but also provides a new insight into an in-depth understanding of the relationship between innovation and economic development, and implies the development potential and application space such a kind of relativistic economic indicator.
Theoretical study of eye-safe 2 μm laser directly pumped by sunlight
Authors: Lin Xue-Tong , Yang Su-Hui , Wang Xin , Li Zhuo , Zhang Jin-Ying ,   School of Optics and Photonics, Beijing Institute of Technology, Beijing 100081, China,   Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology, Beijing 100081, China,   Key Laboratory of Photonics Information Technology, Ministry of Industry and Information Technology, Beijing 100081, China
Published: December 2020

Solar energy has become one of the new types of energy sources for humanity in the future due to its abundant recourse, clean use and huge reserve. Solar-pumped laser has potential applications in free space optical communications, remote sensing and other fields. However, the research on solar-pumped laser is limited to 1 μm band with neodymium-doped material as a gain medium. To expand the output wavelength range of solar-pumped solid-state lasers, thereby expanding their application fields is one of the goals pursued by researchers in the field. According to the analysis of the absorption spectra of existing solid laser materials, we find that the thulium-doped crystals also have strong absorption peaks in visible light band where solar radiation is strong. Therefore, it is possible that solar-pumped laser could also generate output at 2 μm eye-safe wavelength. In this paper, the absorption spectrum and spectral matching of two common laser crystals—Tm:YAG and Tm:YAP with solar spectrum are analysed and calculated. According to the quasi-three-level transition rate equation of thulium ion and the model of solar-pumped laser system, we obtain the theoretical threshold pump power densities of these two crystals to be 1.14 kW/cm3 and 1.434 kW/cm3, respectively. We choose the Tm:YAG crystal with lower threshold pump power density as the gain medium and built a two-stage pumping model with TracePro software. In our model, Fresnel lens is the primary solar light concentrator, and a conical cavity with diffusion reflection surface is used as a secondary concentrator to couple the solar energy to laser crystal. Laser setup parameters such as the distance between the Fresnel lens and the window of conic cavity, length of crystal, taper of conic cavity are optimized with the model. The work in this paper offers a valuable reference for future experimental research of 2 μm solar-pumped laser. Finally, we point out the challenge of the future work. Special attention needs to be paid to the huge thermal effect caused by a large amount of sunlight shining on the Tm:YAG crystal. We could find a new kind of diffuse reflection coolants or use thermally bonded crystals to mitigate thermal effects. It will be the focus of future work.
Generation of ultra-fast pulse based on bismuth saturable absorber
Authors: Yuan Hao , Zhu Fang-Xiang , Wang Jin-Tao , Yang Rong , Wang Nan , Yu Yang , Yan Pei-Guang , Guo Jin-Chuan ,   College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China,   College of Mechatronics and Control Engineering, Shenzhen University, Shenzhen 518060, China,   College of Liberal Arts and Sciences, National University of Defense Technolog, Changsha 410073, China
Published: December 2020

We demonstrate a bismuth (Bi) saturable absorber (SA) for generating ultrafast pulse. The Bi SA is fabricated by the Bi film deposited on the surface of microfibers through using magnetron sputtering. Its nonlinear optical properties are investigated. The as-prepared Bi SA has outstanding nonlinear absorption property demonstrated by the open aperture (OA) Z-scan system at 1500 nm and balanced twin-detector method at 1560 nm. The nonlinear optical property of Bi SA shows that the modulation depth, the nonsaturable losses, and the saturable intensity at 1.5 μm are 14% and 79%, and 0.9 MW/cm2, respectively. Besides, the closed aperture (CA) Z-scan measurement is also implemented to estimate the nonlinear refractive index of Bi film. The Bi film shows that the typical CA/OA curve possesses the feature of peak-valley profile, meaning that the sample with a negative nonlinear refractive index is self-defocusing. In our experiments, the parameters of the nonlinear absorption coefficient β and the nonlinear refractive index n2 are estimated at about 2.38 × 10–4 cm/W and –1.47 × 10–9 cm2/W according to the actual experimental data points, respectively. To further investigate its nonlinear optical property, the microfiber-based Bi SA is embedded into an erbium-doped fiber laser with a typical ring cavity structure. Based on the Bi SA device, the stable ultrafast pulses are generated at 1.5 μm with the pulse width of 357 fs, the output power of 45.4 mW, corresponding to the pulse energy of 2.39 nJ, and the signal-to-noise ratio is 84 dB. The stable soliton pulses emitting at 1563 nm are obtained with a 3-dB and 6-nm spectral bandwidth. The experimental results suggest that the microfiber-based Bi SA prepared by magnetron sputtering deposition (MSD) technique can be used as an excellent photonic device for ultrafast pulse generation in the 1.5 μm regime, and the MSD technique opens a promising way to produce high-performance SA with a large modulation depth, low saturable intensity, and high power tolerance, which are conducible to the generation of high power and ultrafast pulse with high stability.
Analysis of coherent combination characteristics of beam array via tight focusing
Authors: Zhong Zhe-Qiang , Mu Jie , Wang Xiao , Zhang Bin ,   College of Electronics and Information Engineering, Sichuan University, Chengdu 610065, China,   Laser Fusion Research Center, China Academy of Engineering Physics, Mianyang 621900, China,   Science and Technology on Plasma Physics Laboratory, Mianyang 621900, China,   Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
Published: December 2020

In order to obtain focal spot with high power and spot size comparable to wavelength scale, a novel approach to achieving the coherent combination of beam array by tightly focusing is proposed. The physical model of coherent beam combination of beam array via tightly focusing is built up by the use of the vector diffraction integral. Therefore the influences of beam configuration, polarization state, beam width, beam interval and numerical aperture of the tight focusing system on the characteristics of the combined beam are discussed in detail. The results indicate that the coherent combination effect of beam array with linear and circular polarization via tight focusing is the first best, and that with the radial polarization is the second best but that with the azimuthal polarization is the worst. The beam array of linear and circular polarization with rectangle configuration can be tightly focused onto center point, and the beam array with hexagon is also focused onto center point but with lower efficiency. In addition, by enlarging the beam width and the beam interval to a certain extent, the combination efficiency can be increased. By optimizing the beam configuration, beam width and interval, and selecting rational numerical aperture of the tightly focusing geometry, the focal spot with high energy concentration can be obtained with high beam quality and combination efficiency.
Method of measuring absolute distance based on spectral interferometry using an electro-optic comb
Authors: Zhao Xian-Yu , Qu Xing-Hua , Chen Jia-Wei , Zheng Ji-Hui , Wang Jin-Dong , Zhang Fu-Min ,   State Key Laboratory of Precision Measurement Technology and Instruments, Tianjin University, Tianjin 300072, China
Published: December 2020

To explore a new generation of ranging method suitable for industrial applications, in this paper, a spectral interferometry ranging method based on electro-optic (EO) comb is proposed. The mathematical model of EO comb and the principle of spectral expansion are analyzed in detail. Besides, the factors affecting the non-ambiguous range and resolution of the spectral interferometry method are also discussed. According to the theoretical analysis, the resolution of spectral interference ranging is mainly affected by the spectrum width of the optical frequency comb, and the non-ambiguous range is affected by the resolution of the optical spectrum analyzer (equal to the highest sampling rate of the optical spectrum analyzer). In the experiment, triple cascaded EO phase modulator is used to modulate a single frequency laser to generate more than 40 high-power sidebands. Then, the laser spectrum output from the EO modulator is expanded by single mode fiber and high nonlinearity fiber. Owing to the use of erbium doped fiber amplifier between the dispersion compensation fiber (single mode fiber) and the highly nonlinearity fiber, the polarization disturbance does not affect the spectrum width of the optical frequency comb significantly. However, the width of spectrum will be still affected by the phases of light, and the phases of light can be adjusted by the phase shifters in the front of the electro-optic modulators. Finally, the EO comb with a repetition frequency of 10 GHz and spectrum width of 30 nm is obtained. The EO comb can be used as the source of spectral interferometry scheme. Since the repetition frequency of the EO comb is high enough, which can meet the distortion-free sampling of optical spectrum analyzer. Hence, there is no “dead zone” in the measurement range. Besides, the equal frequency interval resampling algorithm and quadratic equation fitting algorithm are used in the data processing. Through the use of these algorithms, we can eliminate the measurement errors caused by non-equal frequency interval sampling of the optical spectrum analyzer and improve the ranging accuracy. The experimental results show that within the range of 1 m, the absolute ranging accuracy of 15 μm can be achieved at arbitrary position.
High resolution imaging based on photo-emission electron microscopy excited by deep ultraviolet laser
Authors: Lü Hao-Chang , Zhao Yun-Chi , Yang Guang , Dong Bo-Wen , Qi Jie , Zhang Jing-Yan , Zhu Zhao-Zhao , Sun Yang , Yu Guang-Hua , Jiang Yong , Wei Hong-Xiang , Wang Jing , Lu Jun , Wang Zhi-Hong , Cai Jian-Wang , Shen Bao-Gen , Yang Feng , Zhang Shen-Jin , Wang Shou-Guo ,   Department of Materials Physics and Chemistry, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China,   State Key Laboratory of Magnetism, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China,   Key Laboratory of Functional Crystals and Laser Technology, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China
Published: December 2020

Magnetic imaging technology based on photo-emission electron microscopy (PEEM) has become an important and powerful tool for observing the magnetic domain in spintronics. The PEEM can get access to real-time imaging with high spatial resolution and is greatly sensitive to the spectroscopic information directly from the magnetic films and surfaces through photoemission process with variable excitation sources. Moreover, the breakthrough in the deep ultraviolet (DUV) laser technology makes it possible to realize domain imaging without the limitation of synchrotron radiation facilities or the direct excitation of photoelectrons due to the high enough photon energy of the source in the current threshold excitation study. In this review article, the deep ultraviolet photo-emission electron microscopy system is first introduced briefly. Then, a detailed study of the magnetic domain observation for the surface of L10-FePt films by the DUV-PEEM technique is presented, where a spatial resolution as high as 43.2 nm is successfully achieved. The above results clearly indicate that the DUV-PEEM reaches a level equivalent to the level reached by X-ray photoemission imaging technique. Finally, a series of recent progress of perpendicular FePt magnetic thin films obtained by the DUV-PEEM technique is provided in detail. For example, a stepped Cr seeding layer is used to form the large-area epitaxial FePt films with (001) and (111) two orientations, where magnetic linear dichroism (MLD) with large asymmetry is observed in the transition area of two phases. The signal of MLD is 4.6 times larger than that of magnetic circular dichroism. These results demonstrate that the magnetic imaging technology based on DUV-PEEM with excellent resolution ability will potentially become an important method to study magnetic materials in the future.
Owning the Street
Authors: Thorpe Amelia
Published: December 2020

How local, personal, and materially grounded understandings about belonging, ownership, and agency intersect with law to shape the city.

In Owning the Street, Amelia Thorpe examines everyday experiences of and feelings about property and belonging in contemporary cities. She grounds her account in an empirical study of PARK(ing) Day, an annual event that reclaims street space from cars. A highly recognizable example of DIY urbanism, PARK(ing) Day has attracted considerable media attention, but not close scholarly examination. Focusing on the event's trajectories in San Francisco, Sydney, and Montréal, Thorpe addresses this gap, making use of extensive fieldwork to explore these tiny, temporary, and yet often transformative urban interventions.

PARK(ing) Day is based on a creative interpretation of the property producible by paying a parking meter. Paying a meter, the event's organizers explained, amounts to taking out a lease on the space; while most “lessees” use that property to store a car, the space could be put to other uses—engaging politics (a free health clinic for migrant workers, a same sex wedding, a protest against fossil fuels) and play (a dance floor, giant Jenga, a pocket park). Through this novel rereading of everyday regulation, PARK(ing) Day provides an example of the connection between belief and action—a connection at the heart of Thorpe's argument. Thorpe examines ways in which local, personal, and materially grounded understandings about belonging, ownership, and agency intersect with law to shape the city. Her analysis offers insights into the ways in which citizens can shape the governance of urban space, particularly in contested environments.

The book's foreword is by Davina Cooper, Research Professor in Law at King's College London.
Dokumentasjon av kulturminneområdet på ID 27272 Taborshamn, Hasvik kommune, Finnmark i 2018 under forskningsprosjektet «Stone Age Demographics»
Authors: Damm Charlotte , Skandfer Marianne
Published: December 2020

Rapport fra registrering og dokumentasjon av kulturminneområdet på Taborshamn beliggende øst for Hasvik på Sørøya. Området beskrives og det gis detaljert informasjon om alle 51 kulturminner. Rapporten inneholder kart over og fotografier av kulturminnene.
Effects of Earthing up and Pruning Systems on Growth and Yield of Tomato (Solanum lycopersicon.)
Authors: Keter I. K. , Abucheli G. Oloo- , Muraya M.
Published: December 2020

Tomato (Solanum lycopersicon) is an important crop cultivated and consumed worldwide. It provides wide variety of nutrients with many health-related benefits like, protection against cancer, maintains blood pressure and reduces blood glucose level in people with diabetes. Despite the importance of tomato, its growth and yield is limited by choice of cultural practices mainly earthing up and pruning system. There is also limited knowledge on the effect of integrating pruning and earthing up on tomato growth and yield. This study investigated the effect of integration of pruning and earthing up on the growth and yield of tomato. A split-plot experimental design, arranged in a Randomized Complete Block Design, with three replications was used. The study investigated two factors i.e. pruning system in the main plot (single stem, double stem, and triple stem) and earthing up in sub-plots. (0 cm, 10 cm, 20 cm, and 30 cm. The findings of the study revealed that earthing up and pruning system had a significant (p ˂ .05) effect on plant height and stem girth diameter at 45, 52, and 59 days after transplanting. The single stem pruning system and earthing up to 30 cm gave the tallest plant height with an average plant height of 69.80 cm in cultivation 1 and 71.50 cm in cultivation 2. Single stem pruning system and earthing up to 30 cm gave the largest stem girth diameter with mean stem girth diameter of 2.16 cm in cultivation 1 and 2.25 cm in cultivation 2. Triple stem pruning system, earthing up to 30 cm recorded the highest number of marketable fruits with 64500 fruits/hectare in cultivation 1 and 64333 fruits/hectare in cultivation 2. To improve tomato growth and development which consequently improves marketable yields, farmers are encouraged to consider triple stem pruning system with earthing up to level 30 cm.
Effect of Aqueous Extract of Costus afer Stems on the Serum Proteins and Bilirubin Levels of High Fat Diet Induced Hyperlipidemic Rats
Authors: Chioma Anyiam C. , Albert Anyiam C. , Ijeoma Onyeneho R.
Published: December 2020

Aim: The effect of aqueous extract of Costus afer stems on total protein, albumin,globulin, total and

conjugated bilirubin levels in diet induced hyperlipidemic rats were studied.

Methodology: Wistar albino male rats (100-135 g) were randomly distributed into 7 groups of 12 rats each. Group I was fed with standard diet as normal control rats and all the other groups were fed with high fat diet (10 g eggyolk/day) for 2 weeks. The plant extract was administered orally at different concentrations of 400, 800 and 1600mg/kg b.w alone and also in combination with the reference drug, Atorvastatin® (0.26mg) to the treatment groups for four weeks.  The serum proteins and bilirubin were observed at specific intervals (2 weeks).

Results: The results revealed significant (p<0.05) increase in the total protein, albumin and globulin concentration after 2 weeks of feeding with high fat diet in rats which were in groups IV and V as compared to normal control rats. Treatment of rats with plant extract showed no significant difference in the total protein concentration of hyperlipidemic test rats while the albumin concentration of rats in group VII increased significantly when compared to the normal and hyperlipidemic control rats. There was no significant difference in the globulin concentration of hyperlipidemic treated rats. After 2nd and 4th week of treatment, the total bilirubin concentrations of rats in groups V and VI (HTR on aqueous extract, 1600 mg/kg and HTR on aqueous extract, 800 mg/kg) decreased significantly when compared with normal and hyperlipidemic control rats. After 2 weeks of treatment, the conjugate bilirubin concentration of rats in group VI (HTR on aqueous extract, 1600 mg/kg) significantly (p<0.05) decreased when compared to the hyperlipidemic control rats.

Conclusions: Hence, this shows that Costus afer stem extract does not have any deleterious effect on tissues and on the analyzed parameters.
Factors Affecting Job Satisfaction: An Exploratory Analysis among Public Bank Employees in Selected Cities of Bangladesh
Authors: Aziz Nabid , Mustafi Mohitul Ameen Ahmed , Hosain Md Sajjad
Published: December 2020

This exploratory study aims to determine the factors affecting the overall perceived job satisfaction of the employees working at different public banks in Bangladesh. The authors carefully selected seven such factors after searching the existing literature. Those seven factors: working hour, fair competition, equal treatment, psychological support & fun, promotional opportunity, benefit package and co-working relationship were considered as the independent variables while overall job satisfaction was considered as the single dependent variable. Primary data were collected from a valid sample of 360 public sector bank employers through a structured questionnaire. Exploratory factor analysis (EFA) using SPSS (24) was utilized in order to validate the items of independent variables and structural equation modeling using AMOS (24) was utilized in order to test the hypothesized relationships between each independent variable and the dependent one. After proper statistical analysis, it was revealed that fair competition, equal treatment, promotional opportunity and working hour can positively and sufficiently influence the perceived overall job satisfaction of Bangladesh public bank employees while the other three factors, psychological stress & frustration, co-working relationship and benefit package were found to have insufficient influence over job satisfaction. The authors are well confident that this explorative study will guide the bank management in satisfying their competent employees in a more effective manner. Implications, limitations, and future directions have been also discussed in the study.
Collection and Processing of Non-timber Forest Products in North Eastern Pakistan of Azad Jammu and Kashmir: An Empirical Study
Authors: Zubair Muhammad , Ansari Ahmad Nawaz , Hussain Syed Bilal
Published: December 2020

Himalayan region has diversity of Non-Timber Forest Products and is considered as biodiversity hotspot. Current research is baseline study providing information on extraction and processing of Non-Timber Forest Products especially medicinal plants in North Eastern Pakistan of Azad Jammu and Kashmir. A total of 60 respondents (local collectors) were selected based on snowball sampling procedure. Results revealed that income generation remained the prime reason for collection of Non-Timber Forest Products in both regions and collectors have to travel up to 4-6km for collection. Most (i.e.,91%) of the respondents collected Non-Timber Forest Products for medicinal reasons in Bagh District whereas vegetable collection (i.e.,86%) is the prime reason for collection in Neelam valley. Non-Timber Forest Products are mostly collected manually during summer for 6-10 hours with frequency of 1-3 times in a season. It was also observed that most of the respondents in Bagh district opted for sun drying whereas sun and shade drying remained a preference of respondents in Neelam valley. It was concluded that a public-private partnership is inevitable for sustainable harvesting, processing and marketing of Non-Timber Forest Products in the region.
Response of Soil Chemical Properties to Rhizobium and Rock Phosphate Fertilizer Application under Green - Grams in Tharaka Nithi County, Kenya
Authors: Mbaka F. K. , Ndukhu H. O. , Oloo-Abucheli G. O.
Published: December 2020

Soil fertility decline is one of the major constraints in agricultural productivity. Biological nitrogen fixation (BNF) in legumes can offer a cost-effective and sustainable means towards soil fertility management. There is limited information on green-gram BNF enhancement through Rhizobium inoculation with rock phosphate fertilizer. The objective of this study was to determine the effects of Rhizobium and rock phosphate fertilizer application on soil chemical properties under green-gram varieties. The study was carried out at Chuka university horticultural research farm in two seasons (November 2019 - January 2020 and February - April 2020). A factorial experiment of 2 x 2 x 2 was laid out in a randomized complete block design (RCBD). There were three factors; varieties (N26 and KS20), rock phosphate (0 and 30 kg P ha-1) and Rhizobium inoculation (0 and 100 g ha-1) making a total of eight treatments which were replicated three times. Soil sampling and analyses were done for soil pH, fixed-N, total nitrogen (TN), exchangeable cations (EC), available Phosphorous (P), total organic carbon (TOC), and exchangeable potassium (K) before planting and after harvesting of green-grams for the two seasons. Data was analysed using GENSTAT 15th edition (P≤0.05). Results from both seasons indicated that combined application of rock phosphate at 30 kg P ha-1 and Rhizobium inoculation at 100 kg ha-1 showed significant (P≤0.05) higher increase in soil chemical properties over other treatments. However, treatment R1P1KS20 recorded significantly higher results in soil pH (7.54), TN (0.58%), TOC (3.45%), P (68.20 ppm) and EC (0.95 CmolKg-1), fixed-N (0.50%) and K (1.75 CmolKg-1). On the other hand treatment R0P0N26 recorded significant (P≤0.05) lower results in soil pH (5.23), TN (0.04%), TOC (1.86%), P (8.76 ppm), EC (0.21 CmolKg-1) and K (0.58 CmolKg-1). Therefore, Rhizobium inoculation in green-grams in combination with rock phosphate is an important legume nitrogen fixation enhancement method. This method is cost effective for farmers in sustainably supplementing nitrogen and phosphorous in their farms for improved soil fertility management. Based on the findings, combining Rhizobium 100g ha-1 and rock phosphate 30 kg P ha-1 with variety KS20 were recommended for a sustainable soil fertility management in Tharaka Nithi County.
Endo-Parasites of Apparently Healthy Wild Birds in Kaduna State, Nigeria
Authors: Assam Assam, , Salamatu Abdu, , Abdu Paul, , Ezealor Augustine,
Published: December 2020

Aims: Wildbirds interaction with poultry increases the likelihood of exchange of parasites between wild birds and poultry highlighting the need to understand wild bird endoparasites to reduce cross-infection at the wild bird-poultry interface. This study investigates the prevalence and diversity of endoparasites among wild birds in Kaduna State to provide baseline data on the wild birds' endoparasites which could be a source of infection to poultry.

Study Design: Wild birds in live wild bird markets, free-flying wild birds and semi-domesticated birds were the samples for endoparasites.

Place and Duration of Study: Birds were sampled in Kaduna State, Nigeria and the samples were analyzed at the helminthology laboratory of Ahmadu Bello University, Zaria between April 2012 and December 2012. 

Methodology: Wild birds faecal samples were examined for endoparasites by the simple flotation method. 

Results: Of the 357 birds sampled, 36.4% were infected with at least one species of endoparasite. Charadriidae (7.1%) and Meleagris gallopavo (23.5%) had the lowest family and species prevalence respectively. Free flying, live poultry markets (LPM) and live wild bird markets (LWBM) birds had a prevalence of 39.1%, 37.2% and 34% respectively. The endoparasites identified were coccidia (30.5%), Ascaridia (5.9%), nematode larvae (0.8%), Capillaria (0.6%); Syngamus, Raillietinia and Trichuris (0.3% for each). There was a significant difference between the prevalence (p = 0.00), mean intensities (p = 0.00) and abundance (p = 0.01) of coccidia and Ascaridia. The prevalence   of multiple infections was 2.0% representing 5.4% of infected birds. The study is first to report  in Kaduna State, Nigeria of Trichuris in Anas platyrhynchos and Raillietina in Laniarius  barbarous.

Conclusion: Wild birds in Kaduna State, Nigeria harbours endoparasites of economic significance to poultry and there is the need for more study of these wild birds’ endoparasites at the wild bird–poultry interface.
Aqueous Extract of Zingiber officinale Roscoe Rhizomes Sold in Ouagadougou Markets: Phytochemical Constituents, Effect on Arterial Pressure and Blood Biochemical Parameters of Wistar Rats
Authors: Tougouma Larba Colette , Ouédraogo Youssoufou , Somé Abel Andouormwine , Belemnaba Lazare
Published: December 2020

The aim of this study was to exhibit cardiovascular effects of aqueous extract of Zingiber officinale rhizome sold in Ouagadougou markets (Burkina Faso). Phytochemical constituents and some blood biochemical parameters were also investigated. Colorimetric method was used for phytochemical screening. Extract was prepared and orally administered on Wistar rats. Arterial pressure and cardiac rhythm were measured using Ugo Basile Blood Pressure Recorder 58500. Biochemical parameters were performed using Mindray BA-88A, Semi-auto Chemistry Analyzer. Triterpenes and/or sterols, and saponosides were present in aqueous extract of the plant. We also found very significative hypotension effect on rat mean arterial pressure, when plant extract was administered at 400 mg/kg bw (p ˂ 0.01). When extract was administered after a hypertension induced by L-NAME, we observed a high significative antihypertensive effect (p ˂ 0.001) at 200 and 400 mg/kg bw. This effect was comparable to captopril inhibition of L-NAME induced hypertension. However, in all cases, we did not observe any significative variation of heart rate. For biochemical parameters, we did not find any effect, excepted a significant increase of phosphoremia at 400 mg/kg bw and after L-NAME administration (highly significant). Our results confirm literature data and corroborate traditional uses of Z. officinale sold in Ouagadougou markets. They suggest that antihypertensive effect of AEZO is mainly supported by vascular physiology components.
Spermicidal and Antibacterial Effects of Oncoba welwitschii Oliv. (Salicaceae)
Authors: Kabena Odette N. , Nyakembe Naomie E. , Amogu Jean Jacques D. , Asamboa Lionel S. , Lengbiye Emmanuel M. , Mboloko Justin E. , Mpiana Pius T. , Lukoki Félicien L.
Published: December 2020

Aim: The aim of this work is to evaluate the spermicidal, antimicrobial activity of Oncoba welwitchii Oliv. This will justify its use on reproductive health especially in the occurrence of infertility and the imbalance of vaginal flora. Carried out at the Department of Biology of the Faculty of Sciences of the University of Kinshasa, between January and May 2019, this study was initiated to determine the effect of the use of O. welwitchii Oliv. on human spermatozoa and vaginal microorganisms.

Methodology: The leaves of O. welwitchii Oliv. were collected and identified at University of Kinshasa. The spermicidal effect was performed by the Sander-Cramer method and antibacterial activity were evaluated by liquid dilution method.

Results: The results revealed that the juice of the leaves of O. welwitchii Oliv. have a spermicidal effect, as this juice reduce the initial mobility of the spermatozoids after 60 minutes of the exposure from 72±12% to 1±2% and their initial viability from 74±11% to 10±18%. This juice has shown bacteriostatic effects against Escherichia coli and Staphylococcus aureus (MBC/MIC > 4) and bactericidal effects against Lactobacilus acidophilus (MBC/MIC ≤ 4).

Conclusion: This study gives additional information on the phytochemistry composition and a spermicidal effects of O. welwitchii Oliv. The spermicidal effects of this plant could be associated to its acidity.

It should be noted that to the best of our knowledge, no study on the phytochemistry of O. welwitchii Oliv. is available in the literature.
Planning Bus Transit Unit in Sprawling Townships; Khurdha Road Junction, Odisha; India
Authors: Mishra Siba Prasad , Kumar Chandan , Sethi Kumar Ch. , Siddique Mohammad
Published: December 2020

The customized buses (CBs) is a novel approach of community transportations at present and have become popular mode of expanded municipal conveyance, modernized, gorgeous and traffic services. The CB is planned by combining long term demand and passenger’s comforts and necessities. Based on analysis of the passengers travel data from inland and abroad at a focused point, the development of the CB is to be planned and proposed in a small town like Khurdha Road Junction (Jatni) in Odisha.. Present study points out the glitches linked with the operation and maintenance, expansion of CBs depending upon increase in numbers of travelers and other factors like stop assortment, line plan, schedules, and the impact of the proposed new public bus transit system. Traffic excellence factors, like average speed, delays, traffic jamming, travel time, and cost were considered while planning for the new transit bus terminal. The small towns around the smart city Bhubaneswar is gazing at a grave commuting conundrum. The planning and construction of the bus transit at Khurdha Road junction (Jatni) is developed to cope with the sprawling township and save the roads from severe traffic jam. Economic analysis with environmental Impact assessment of the project is done.
Light Emitting Diode (LED) Bulb Aspiration in Northern Ghana: A Case Report and Literature Review
Authors: Adjeso Theophilus , Issaka Adamu
Published: December 2020

Light emitting diode (LED) bulb is an unusual cause of foreign body aspiration. We present a case of a 6-year-old boy who reported with a four-day history of difficulty in breathing and cough following a LED bulb aspiration retrieved via rigid bronchoscopy. This present case suggests that LED bulb should be considered in the differential diagnosis of foreign body aspirations in our environment.