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More than 25 million tons per year of phosphorus (P) fertilizer from phosphate rock is applied to meet the increasing global food and wood demand despite limited phosphate rock reserves. Yet, the fate of applied inorganic P fertilizer and its drivers have never been systematically explored globally, although doing so can help improve P fertilizer use efficiency. Here, we synthesized 987 field P-addition observations and found that, globally, on average, 12.6% of added inorganic P fertilizer was taken up by plants, 67.2% was stored in the soil and 4.4% was lost. Increased P-addition quantity was the main reason for the decline in plant P uptake. Soil pH and bulk density also modulate the flow of added P to plants, soil, and leaching/runoff loss. Our findings highlight the urgent need to improve P fertilizer use efficiency globally by lowering the P fertilization rate, especially on near-neutral soils with low bulk density.

In this paper, a 16-channel 40 Gb/s wave division multiplexing lightwave system is simulated using OptiSystem version 14 and optimized. This paper proposes a Pareto optimization and particle swarm optimization algorithms to find optimum launch power for minimum bit error rate (BER). However, simulation results show that the proposed algorithms proved to be a good solution and take considerable computational time to converge and reach global optimum. It is concluded that return-to-zero modulation format has higher-quality factor, lower BER, and lower distortion and it is less affected by the fiber nonlinearity.

Background Tobacco use is associated with medical, social and economic problems. There is paucity of data on tobacco use among undergraduates in northern Nigeria. This study assessed pattern and predictors of tobacco use among undergraduates in Zaria, North-western Nigeria.Method It was a cross-sectional study of undergraduates in three tertiary institutions. Multi-stage sampling technique was used to select 1,080 undergraduates. Data was collected using a questionnaire adapted from Global Adult Tobacco Survey and Global Youth Tobacco Survey. Bi-variate analysis was used to identify independent variables showing statistically significant association with current tobacco use. These were entered into step-wise logistic regression.Results Their median age was 24 years (range:15–47). Prevalence of current tobacco use was 27.0%. About 58.7% smoked tobacco daily and 40.0% used smokeless tobacco daily. Commonest places where tobacco was used were off campus accommodation (30.2%), social center (30.2%) and bar or club (28.1%). Predictors of tobacco use were being a male [2.64(1.82–3.84)], married [2.33(1.49–3.70)], experiencing tobacco promotional activity [1.56(1.12–2.17)], willing to use promotional objects [2.06(1.35–3.14)], using of promotional objects [2.74(1.90–3.96)], and exposure to secondhand smoke [14.10(4.16–47.81)]. Predictors of non-use of tobacco were spending two years or less awaiting university admission [0.65 (0.46–0.91)], parents currently together [0.48(0.33–0.69)], and supporting ban on tobacco [0.34 (0.23–0.48)].Conclusion Prevalence of tobacco use and expenditure on tobacco were high. University authorities should commence programs to identify tobacco users and encourage cessation. The findings also highlight the need to establish effective tobacco surveillance system that includes students of tertiary institutions.

Background: Grazing exclusion is a practical approach to restore vegetation in degraded grasslands and enhance soil organic carbon (SOC) sequestration. However, the dynamics and drivers of SOC in grasslands after grazing exclusion have not been well documented, especially in ecosystems with cold climates. Methods: Here, we established 14 paired treatments (grazing exclusion vs. free-grazing) along a 600-km transect in the northeastern zone of the Qinghai-Tibet Plateau. After six years, we analyzed vegetation biomass dynamics and measured the soil physicochemical properties and organic C concentration across three depths (0–10, 10–20, and 20–30 cm). Results: Grazing exclusion significantly increased above- and belowground biomass (139.85% and 43.30%, respectively), pH (1.38%), total phosphorus (3.29%), nitrate nitrogen (18.03%), and ammonium nitrogen (17.81%), but significantly decreased soil bulk density (2.43%) and clay content (10.49%), particularly in 0–30 cm. Specifically, SOC concentrations positively responded to grazing exclusion (0–10 cm) in 9 of the 14 sites evaluated. The effects of grazing exclusion on SOC concentrations were significantly higher in areas with a mean annual temperature (MAT) below 0 °C compared to those in sites with a high MAT (> 0 °C). The SOC concentrations significantly correlated with the mean annual precipitation (MAP) in both treatments, but these correlations diminished with increasing soil depth. Ridge regression analysis showed that soil chemical properties (e.g., total nitrogen and phosphorus) positively influenced SOC accumulation, while MAT negatively influenced it after grazing exclusion. Path analysis further revealed that MAT indirectly regulated SOC dynamics via soil chemical properties. Conclusions: Our study highlights that grazing exclusion results in an asynchronous SOC and plant biomass accumulation and may be more beneficial for SOC sequestration in Qinghai-Tibet Plateau grasslands with lower temperatures. Also, humid climates promote SOC concentration in alpine grasslands. These results could help develop management practices and policies that promote sustainable grassland management.

MgO and sepiolite doping optimized biochar’s surface properties for phosphorus (P) retention and slow releaseThe potential formation of Mg-PO4phases on the optimized biochar surface regulated P retention and releaseMgO and sepiolite-ptimized biochars increased soil available P by promoting microbial P mineralization and solubilization.

There are rising concerns about the negative environmental impacts of excessive N fertilizers used in agriculture. However, perennial crops require periodic large N doses for optimum growth. Hence, minimizing N application and regulating its long-term availability using N-cycling-mediating bacteria is a viable option that remains unexplored. We explored the comparative potentials of biochar and manure to provide a conducive condition for Bacillus subtilisand Bacillus licheniformisto improve their effects on N-cycling enzyme activity, the distribution of indigenous N-cycling-related bacteria, and long-term N availability for the growth of Nageia nagiafter one year of single N dose. Results showed that NH4+-N did not vary across the treatments. While NO3--N showed no variation between the fertilizer+biochar (FB) and fertilizer+manure (FM) treatments, dissolved organic-N (DON) increased in FB. Inoculation+fertilizer+biochar (FBI) induced a potential N-cycling enzyme activity, hence, an increase in NO3--N, DON, and amino acid-N concentrations compared to inoculation+fertilizer+manure (FMI). This was associated with increased plant growth and leaf-N concentration in the inoculated treatments. Higher N-cycling due to Bacillusspp. inoculation increased the diversity of soil bacteria in FMI compared to FBI and other treatments. However, an increase in the relative abundance of some key nitrification-related bacterial taxa in FBI (Betaproteobacteria, Gammaproteobacteria, and Actinobacteria) was associated with higher N-cycling enzyme activity, NO3--N, DON, and amino acid-N concentrations compared to FMI. Due to low persistence, the long-term effect of Bacillusspp.on N release was mainly indirect, through their stimulatory effect on N-cycling enzyme activity and bacterial community. Therefore, periodic inoculation in biochar amended soils could be important in sustaining long-term N availability.

Gas hydrates are considered “near-future energy resources” due to their vast existence all around the world. Recently, China has tested gas production from methane hydrate-bearing clayey silts via horizontal well technology for the first time. This study aims to investigate the effect of well configuration on gas production from the Black Sea gas hydrates. Mainly, two different hydrate-bearing models (single-layer homogeneous hydrate-bearing sands and multilayer hydrate-bearing turbidite) were constructed in this study. Gas production numerical simulations were held using the TOUGH + HYDRATE simulator. Gas production via the horizontal well in single-layer homogeneous hydrate-bearing sand was higher compared to the vertical well case at early stages. However, fast depressurization via the horizontal well caused a rapid decline in reservoir temperature and hydrate dissociation rate. Then, local hydrate reformation was detected near the wellbore. In the later periods of gas production, higher gas production with the vertical well was obtained. The clay layers in the heterogeneous methane hydrate reservoirs (alternating sand and clay layers in turbidite) behave like a barrier to depressurization with a horizontal well.

The aim of the present study is to investigate the ameliorative potential of the aqueous extract of Indigofera tinctoria(IT) in aging-induced inflammation and its associated cardiac hypertrophy and fibrosis. Young (3-month-old) and aged (24–26-month-old) male Wistar albino rats were grouped into young control, aged control, aged + IT, and young + IT. The animals in the supplementary groups received 200 mg/kg BWT of aqueous extract of IT orally once a day for 21 days. Aged animals showed prolonged QT interval and increased weight and volume of the heart with a thickening ventricular wall. Infiltration of leukocytes and increased cardiomyocyte diameter and decreased numerical density along with cardiomyocyte apoptosis and increased collagen accumulation were also seen in aged myocardium when compared to the young. The expression profile of various pro-inflammatory cytokines such as IL-6, IL-1β, TNF-α, NFκB, and iNOS was increased with a concomitant reduction in IL-10 expression in the aged compared to the young. In addition, a marked increase in ROS generation, TGF-β, and α-SMA levels is evident in the aged myocardium. These pathological changes were greatly reversed in aged animals supplemented with IT. Furthermore, the aged + IT group showed repression of pro-inflammatory markers with a subsequent increase in IL-10 expression. Contrarily, no marked changes were observed between young and young + IT groups. Taken together, it is concluded that the aqueous extract of Indigofera tinctoriasuppresses cardiac fibrosis and hypertrophy by repressing the inflammation and its associated activation of TGFβ and myofibroblast conversion.

Numerous researchers have investigated switched reluctance motors (SRMs) as a competitor to other electrical motors for usage in electric and hybrid vehicle appliances. SRMs are fault-tolerant and have a broad operating speed range. However, they have numerous drawbacks, such as high nonlinearity in machine models, complex control, and torque ripple. This study aims to improve the SRM drive system to attain maximum torque per ampere in a wide speed range. In the design and control of SRMs, maximizing torque per ampere (MTPA) is a crucial objective. MTPA refers to the strategy of achieving the maximum possible torque output for a given current input (amperes). This is essential for enhancing the efficiency and performance of the motor. The paper focuses on achieving MTPA in an SRM drive system-based commutation angle control. Utilizing a bacterial foraging optimization algorithm (BFOA), the suitable commutation angles at each operation point are determined. The intended technique is straightforward to realize and does not require complex algorithms. Simulation comparisons on an 8/6 SRM are also presented to validate the intended control technique. The results indicate that the MTPA has been enhanced by 6.961% compared to the conventional method.

The inherent features of the Switched Reluctance Motor (SRM) make it a promising applicant for further exploration and examination in various industrial sectors, to mention but a few electric vehicles. The mechanical development of this motor is characterized by its simplicity and cost-effectiveness. Including current controllers within an SRM drive control system is of utmost importance due to their substantial influence on drive performance, dynamic response, and noise and vibration performance. This study aims to improve the SRM drive system to achieve reliability and efficiency. A complete SRM drive system is designed, constructed, and evaluated to accomplish this objective. The contribution of this study is that the consequence of the current control band of hysteresis current control (HCC) on the phase current has been intensely investigated on high-frequency torque ripple, average torque and average switching frequency. This investigation has been performed simultaneously with soft-hysteresis current control and hard-hysteresis current control. Simulation results proved that the soft HCC gives the best results. A trade-off between switching frequency and high-frequency torque ripple has been performed based on choosing the best current control of the proposed model.

Evolution of the penis in sexual method of reproduction had showed complex developmental processes, leading to extreme species variation. The presence and absence of the os penis vary in taxa within mammals indicate adaptive value of the mammalian penis bone, and understanding the diversity is challenging. Surprisingly, little is known about its details. Comparative analysis of the penis with special reference to the os penis (penile baculum) was analyzed in monkey (Macaca radiata), rat (Rattus norvegicus), and bat (Pipistrellus mimus). In monkey, the baculum appears like a miniature of a long bone, a clear central medullary cavity, and surrounded by osteons. Similarly, the baculum in rat showed a medullary canal and surrounded by smaller channels of osteons. In bat, it is seated over the corpus spongiosum that shows a small diameter channel which forms the main lamellar bone and appears to be a single osteon or Haversian system. Though microanatomical examination revealed that the presence of vascular and non-vascular structures contribute for penile erection, the presence of the os penis would be helpful for the penis erection and stiffness and vaginal friction. Anatomical relationship to other penile elements and its specific functional significance and the explanation for this general adaptive diversity across species is challenging.

Two new configurations for the design of biquad filters with high input impedance are presented. The first configuration can synthesize low-pass and high-pass filter functions according to the passive components used. The second one can synthesize a band-pass filter function. The proposed configurations employ only one differential difference current conveyor (DDCC) as active elements and minimum number of passive elements, namely two resistors and two capacitors. Another filter topology based on DDCC is presented that allows modifying the quality factor without changing its natural frequency. All the filters enjoy low sensitivities. SPICE simulation results are given to confirm the validity of the analysis and to point out the high performance of the filters.Two new configurations for the design of biquad filters with high input impedance are presented. The first configuration can synthesize low-pass and high-pass filter functions according to the passive components used. The second one can synthesize a band-pass filter function. The proposed configurations employ only one differential difference current conveyor (DDCC) as active elements and minimum number of passive elements, namely two resistors and two capacitors. Another filter topology based on DDCC is presented that allows modifying the quality factor without changing its natural frequency. All the filters enjoy low sensitivities. SPICE simulation results are given to confirm the validity of the analysis and to point out the high performance of the filters.

In this work, a voltage-mode canonical first-order all-pass filter is presented. The filter contains only a single resistor, a single capacitor, and a single differential difference current conveyor (DDCC). No passive component-matching constraints are required. A complementary metal oxide semiconductor CMOS implementation of a DDCC is given to simulate the proposed circuit with a Spice simulation program whose results illustrate the high performance of the circuit.