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Cereal area and nitrogen use efficiency are drivers of future nitrogen fertilizer consumption

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Science China(Life Sciences) 2005年第Z2期48卷 745-758页

作者： Achim Dobermann Kenneth g.Cassman Department of Agronomy and Horticulture University of Nebraska-Lincoln P.O.Box 830915LincolnNE 68583-0915USA

At a global scale, cereal yields and fertilizer N consumption have increased in a near-linear fashion during the past 40 years and are highly correlated with one another. However,large differences exist in historical trends of N fertilizer usage and nitrogen use efficiency (NUE)among regions, countries, and crops. The reasons for these differences must be understood to estimate future N fertilizer requirements. global nitrogen needs will depend on: (i) changes in cropped cereal area and the associated yield increases required to meet increasing cereal demand from population and income growth, and (ii) changes in NUE at the farm level. Our analysis indicates that the anticipated 38% increase in global cereal demand by 2025 can be met by a 30% increase in N use on cereals, provided that the steady decline in cereal harvest area is halted and the yield response to applied N can be increased by 20%. If losses of cereal cropping area continue at the rate of the past 20 years (-0.33% per year) and NUE cannot be increased substantially, a 60% increase in global N use on cereals would be required to meet cereal demand. Interventions to increase NUE and reduce N losses to the environment must be accomplished at the farm- or field-scale through a combination of improved technologies and carefully crafted local policies that contribute to the adoption of improved N management; uniform regional or national directives are unlikey to be effective at both sustaining yield increases and improving NUE. Examples from several countries show that increases in NUE at rates of 1% per year or more can be achieved if adequate investments are made in research and extension. Failure to arrest the decrease in cereal crop area and to improve NUE in the world's most important agricultural systems will likely cause severe damage to environmental services at local, regional, and global scales due to a large increase in reactive N load in the environment.

关键词： nitrogen, cereals, nitrogen use efficiency, fertilizer requirements, global food security.

Using a Software-Defined Air Interface Algorithm to Improve Service Quality

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Intelligent Automation & Soft Computing 2023年第2期35卷 1627-1641页

作者： Madiraju Sirisha p.Abdul Khayum Department of ECE Jawaharlal Nehru Technological UniversityAnanthapuramuTelaganaIndia Department of ECE G.Pulla Reddy Engineering CollegeKurnoolA.P.India

In the digital era,the Narrowband Internet of Things(Nb-IoT)inﬂu-ences the massive Machine-Type-Communication(mMTC)features to establish secure routing among the 5g/6g mobile *** supports global coverage to the low-cost IoT devices distributed in terrestrial *** key trafﬁc char-acteristics include robust uplink,moderate data rate/device,extremely high energy efﬁciency,prolonging device lifetime,and Quality of Service(QoS).This paper proposes a Deep Reinforcement Learning(DRL)combined software-deﬁned air interface algorithm applied on the switching system,satisfying the user require-ment and enabling them with the network resources to extend quality of service by choosing the most appropriate quality of service *** this framework,Non-Orthogonal Multiple Accesses(NOMA)and Rate-Splitting Multiple Access(RSMA)are combined to accommodate massive(Nb-IoT)devices that can be uti-lized the entire resource(frequency band)for tackling the unknown dynamics *** proposed algorithm instantly assigns the network resources per user requirements and enhances selecting the best quality of service metric ***,it has potential beneﬁts of high scalability,low latency,energy efﬁciency,and spectrum utility.

关键词： DRL NOMA-RSMA nb-IoT mMTC QoS

Development and Validation of Amlodipine Impurities in Amlodipine Tablets Using Design Space Computer Modeling

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American Journal of Analytical Chemistry 2016年第12期7卷 918-926页

作者： Chamarthi R. p. Kishore g. V. Krishna Mohan Department of Chemistry K.L. University Vaddeswaram India

A rapid, sensitive, robust, rugged and linear HpLC method is developed using QbD approach and validated as per ICH for the estimation of amlodipine impurities in tablet dosage form. phosphate buffer with triethyl amine adjusted to pH to 2.8 is used as the mobile phase and 3μ particle size C18 column of 150 mm length and 4.6 mm internal diameter is used. Using photo diode array (pDA) detector, the compounds are monitored at 340 nm. All impurities are well separated and flow gradient has been optimized to obtain the acceptable resolution between impurities and amlodipine. Diluent was chosen, based on the impurity peak shapes and recoveries. Test concentration and injection volume have been optimized to obtain limit of quantification (LOQ) values below the reporting threshold.

关键词： HpLC LOQ QbD Reporting Threshold

The Effect of Microbial Inoculants Applied at Ensiling on Sorghum Silage Characteristics and Aerobic Stability

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Agricultural Sciences in China 2002年第10期1卷 1174-1179页

作者： Ashbell g Weinberg Z g Forage preservation and By-products Research Unit The Volcani CenterBet Dagan 50250 IsraelForage Preservation and By-products Research Unit The Volcani CenterBet Dagan 50250 Israel

Whole crop forage sorghum (Saccharatum) cultivar FS5 was harvested at the soft dough stage of maturity. The sorghum was chopped to approximately 2 cm pieces and ensiled under laboratory conditions in 1.5 L Weck glass jars. At ensiling, it was treated with two commercial microbial inoculants: inoculant A and inoculant B. The inoculants were applied at 2 × 105 colony forming units g-1 DM. Silage with no additives served as a control. Three jars per treatment were opened on days 2, 4, 8, 15 and 60 post-ensiling to study fermentation dynamics. After 60 days of ensiling, the silages were analyzed and subjected to an aerobic stability test lasting 5 days. Results showed that both inoculants caused a more rapid rate of pH decline and a higher amount of lactic acid production. Silages treated with each inoculant produced a little more CO2 and resulted in more glucose loss as compared with the control. Addition of inoculants did not influence (p > 0.05) the ash and crude protein contents, but tended to decrease the concentration of acetic acid (p ppropionic acid (ppges treated with inoculant A possess the more DM loss, and the higher yeast counts upon aerobic exposure. Silage treated with inoculant B had the most DM (pppppprove the fermentation but might impair the aerobic stability for sorghum ensilage.

关键词： Sorghum Silage Microbial inoculants

Improved Osteointegration of Ti-6Al-4V-implants of Different Surface Texture by the Use of Bone Morphogenetic protein-3 (BMp-3)

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Journal of Wuhan University of Technology(Materials Science) 2005年第B12期20卷 301-303页

作者： Esenwein S A Esenwein S Herr g Hauser J Muhr g Hartwig C-H Department of Surgery BG Trauma Center Bergmannsheil University Hospital Buerkle-de-la-Camp-Platz 1 D-44789 Bochum Germany Dental practice Am Obstmarkt 5 D-71522 Backnang Germany Advanced Tissue Regeneration gmbH Turmstr. 16 D-35578 Wetzlar Germany Department of Orthopaedics Michaelis-Hospital Eichenstrasse 34 D-20244 Hamburg Germany

Half of altogether 60 cylindrical implant devices made of titanium-aluminum-vanadium alloy （ Ti-6Al-4V） were plusna-sprayed with a hydroxyapatite-couting and the other half had a corundum blasted porous surface. 15 implants of each group of the titanium test buplants were coated with 230 μg porcine, high-purified BMp- 3-precipitute per implant. In each case a BMp- 3-couted and an uncoated control-device were implanted into the femoral part of the putellofemoral joint of the right and left leg of 30 adult giant rabbits. Histomorphological and histomorphometrical we found in both groups with BMp- 3-coated test devices an improved osteointegrution. Stutistical evaluation using the t-test for matched samples showed 5 weeks after surgery a significant higher volume of tony formed bone of the BMp- 3-coated corundum- blasted or hydroxyapathe- coated Ti- 6Al- 4 V test devices compared to the non-couted controls of the same t）pe （p 〈 0.01, t-test for matched samples）. In both implant groups with BMp-couting a synergetic effect was verifiable although the bone ongrowth in the hydroxyaputite coated implants was more extensive than in the corundum blasted implants. Light microscopy demonstrated osteointegrution without connective tissue membrane around the surface of the implants. Our results indicate that composite metal implants,as used in endoprosthetics and implantology , are suitable carriers for BMp- 3 and im proved fixation of the implants can be achieved. The hydroxyapatite surface is superior to the corundum-blasted surface with regards to the observed parameters because of its pronounced bioactivity and its osteoconductive characteristics.

关键词： bone morphogenetic protein-3 BMp- 3 hydroxyapatite osteointegration surface coating bone ingrowth implantology

Assessment of soil erosion in a tropical mountain river basin of the southern Western ghats,India using RUSLE and gIS

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geoscience Frontiers 2018年第3期9卷 893-906页

作者： Jobin Thomas Sabu Joseph K.p.Thrivikramji EWRE Department of Civil EngineeringIndian Institute of Technology MadrasChennai600036Tamil NaduIndia Department of Environmental Sciences University of KeralaThiruvananthapuram695581KeralaIndia Center for Environment and Development Thiruvananthapuram695013KeralaIndia

Revised Universal Soil Loss Equation(RUSLE) model coupled with transport limited sediment delivery(TLSD) function was used to predict the longtime average annual soil loss, and to identify the critical erosion-/deposition-prone areas in a tropical mountain river basin, viz., Muthirapuzha River Basin(MRB; area=271.75 km^2), in the southern Western ghats, India. Mean gross soil erosion in MRB is 14.36 t ha^(-1) yr^(-1), whereas mean net soil erosion(i.e., gross erosion-deposition) is only 3.60 t ha^(-1) yr^(-1)(i.e., roughly 25% of the gross erosion). Majority of the basin area(~86%) experiences only slight erosion(positional environment for the eroded sediments(e.g., the terraces of stream reaches, the gentle plains as well as the foot slopes of the plateau scarps and the terrain with concordant summits). Although mean gross soil erosion rates in the natural vegetation belts are relatively higher, compared to agriculture, settlement/built-up areas and tea plantation, the sediment transport efficiency in agricultural areas and tea plantation is significantly high,reflecting the role of human activities on accelerated soil erosion. In MRB, on a mean basis, 0.42 t of soil organic carbon(SOC) content is being eroded per hectare annually, and SOC loss from the 4th order subbasins shows considerable differences, mainly due to the spatial variability in the gross soil erosion rates among the sub-basins. The quantitative results, on soil erosion and deposition, modelled using RUSLE and TLSD, are expected to be beneficial while formulating comprehensive land management strategies for reducing the extent of soil degradation in tropical mountain river basins.

关键词： Soil erosion RUSLE Transport limited sediment delivery Muthirapuzha river basin Western ghats Kerala

Exposure of Kenyan population to aflatoxins in foods with special reference to Nandi and Makueni counties

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Food Quality and Safety 2017年第2期1卷 131-137页

作者： E.K.Kang’ethe M.gatwiri A.J.Sirma E.O.Ouko C.K.Mburugu-Musoti p.M.Kitala g.J.Nduhiu J.g.Nderitu J.K.Mungatu V.Hietaniemi V.Joutsjoki H.J.Korhonen Department of public Health Pharmacology and ToxicologyNairobiKenya Jomo Kenyatta University of Agriculture and Technology NairobiKenya Ministry of Agriculture Livestock and Fisheries Veterinary Laboratories KabetePrivate Bag KabeteNairobiKenya Natural Resources Institute Finland LUKEJokioinenFinland

Aflatoxins cause acute and chronic health and production effects in humans and animals,*** study reports on the exposure of the Kenyan population to the two mycotoxins in two counties(Nandi and Makueni)using children younger than 5 years as the proxy.A questionnaire was administered,which captured knowledge of the incidences of acute aflatoxin poisoning,food consumption *** of aflatoxin in samples of urine,breast milk,maize,sorghum,and millet was done using cELISA and *** and sorghum are used in the weaning formula of *** difference in consumption of maize-and sorghum-based diets in children between younger than 1 and between 1 and 5 years was significant with p=0.037 and p=0.002,respectively,in Nandi and *** children younger than 5 years,the consumption of maize ranged from 0.1 to 0.25 kg per person per day in Nandi and Makueni with an aflatoxin exposure rate of 0.011 and 0.49μg per kg body weight(bwt)per day,*** exposure to aflatoxin through milk for children younger than 5 years was 4×10^(−4) and 1×10^(−4)μg per kg bwt per day in Makueni and Nandi,*** exposure of nursing children through breast milk was 6×10^(−3) and 1×10^(−6)μg per kg bwt per day in Makueni and Nandi,*** younger than 30 months in Makueni had 1.4 times higher levels of aflatoxin M1(AFM1)in urine than those of the same age in *** stunting and severe stunting rates in Makueni and Nandi were 28.7%,18.5%and 30.7%,16.5%,***,there is need for urgent mitigation measures,a constant surveillance program,strict regulations,and awareness creation directed at poor households to reduce dietary exposure to mycotoxins.

关键词： Aflatoxins Contamination Exposure Kenya.

Best C^(4+) and C^(5+) Beams of the Kei2 ECR Ion Source

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Chinese physics C 2007年第S1期31卷 170-173页

作者： g.S.Taki p.R.Sarma A.g.Drentje T.Nakagawa p.K.Ray R.K.Bhandari Variable Energy Cyclotron Centre Block-AF BidhannagarKolkata-700064India Kernfysisch Versneller Instituut GroningenNetherlands Institute of physical and Chemical Research(RIKEN) Wakoshi-3510198Japan Bengal Engineering and Science University ShibpurHowrah-711103India

Earlier we reported an ion current jump which was observed at a fixed negative biased disc potential in the 6.4gHz ECR ion source at VECC,*** a recent experiment with neon ions,we measured the time spectra of the ion current and observed the presence of a burst frequency in the kilohertz *** frequency shows a correlated jump with the ion current jump described *** interesting feature is that the observed burst frequency shows a good linear correlation with the extracted ion *** higher the ion current,the higher is the burst *** means that current per burst is a constant factor;when there are more number of bursts,the current also increases.

关键词： biased disc ion current burst frequency

N-acetyl-L-cysteine combined with mesalamine in the treatment of ulcerative colitis: Randomized,placebo-controlled pilot study

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World Journal of gastroenterology 2008年第18期14卷 2851-2857页

作者： Luis g guijarro Jose Mate Javier p gisbert Jose Luis perez-Calle Ignacio Marín-Jimenez Encarna Arriaza Tomás Olleros Mario Delgado Maria S Castillejo David prieto-Merino Venancio gonzalez Lara Amado Salvador pea Department of Biochemistry and Molecular Biology CIBERehd Alcalá University Alcalá de Henares Madrid Spain gastroenterology Unit CIBERehd La Princesa University Hospital Autonomous University Madrid Spain gastroenterology Unit Gregorio Maraón University Hospital Complutense University Madrid Spain group Farmasierra SL. Ctra N-Ⅱ Km 26.200 San Sebastián de los Reyes Madrid Spain Laboratory of Immunogenetics Department of Pathology VU University Medical Center Amsterdam The Netherlands

AIM: To evaluate the effectiveness and safety of oral N-acetyl-L-cysteine (NAC) co-administration with mesalamine in ulcerative colitis (UC) patients. METHODS: Thirty seven patients with mild to moderate UC were randomized to receive a four-wk course of oral mesalamine (2.4 g/d) plus N-acetyl-L-cysteine (0.8 g/d) (group A) or mesalamine plus placebo (group B). patients were monitored using the Modified Truelove-Witts Severity Index (MTWSI). The primary endpoint was clinical remission (MTWSI ≤ 2) at 4 wk. Secondary endpoints were clinical response (defined as a reduction from baseline in the MTWSI of ≥ 2 points) and drug safety. The serum TNF-α, interleukin-6, interleukin-8 and MCp-1 were evaluated at baseline and at 4 wk of treatment. RESULTS: Analysis per-protocol criteria showed clinical remission rates of 63% and 50% after 4 wk treatment with mesalamine plus N-acetyl-L-cysteine (group A) and mesalamine plus placebo (group B) respectively (OR = 1.71; 95% CI: 0.46 to 6.36; p = 0.19; NNT = 7.7). Analysis of variance (ANOVA) of data indicated a significant reduction of MTWSI in group A (p = 0.046) with respect to basal condition without significant changes in the group B (p = 0.735) during treatment. Clinical responses were 66% (group A) vs 44% (group B) after 4 wk of treatment (OR = 2.5; 95% CI: 0.64 to 9.65; p = 0.11; NNT = 4.5). Clinical improvement in group A correlated with a decrease of IL-8 and MCp-1. Rates of adverse events did not differ significantly between both groups. CONCLUSION: In group A (oral NAC combined with mesalamine) contrarily to group B (mesalamine alone), the clinical improvement correlates with a decrease of chemokines such as MCp-1 and IL-8. NAC addition not produced any side effects.

关键词： Ulcerative colitis Interleukin Mesalamine N-acetyl-L-cysteine