Mechanistic understanding of iron toxicity tolerance in contrasting rice varieties from Africa: 1. Morpho-physiological and biochemical responses

Iron (Fe) is a fundamental element involved in various plant metabolic processes. However, when Fe uptake is excessive, it becomes toxic to the plant and disrupts cellular homeostasis. The aim of this study was to determine the physiological and biochemical mechanisms underlying tolerance to Fe toxicity in contrasting rice varieties adapted to African environments. Four varieties (CK801 and Suakoko 8 (tolerant), Supa and IR64 (sensitive)) selected from our previous work were analysed in more detail, and the first part of this study reports morphological, physiological and biochemical responses induced by Fe toxicity in these four varieties. Morphological (shoot length, root length, number of lateral roots), physiological (photosynthesis rate, stomatal conductance, transpiration rate, fluorescence, relative water content and cell membrane stability) and biochemical (tissue Fe, chlorophyll pigments, soluble sugars, protein and starch) traits were measured, as appropriate, on both shoot and root tissues and at different time points during the stress period. Fe toxicity significantly (P ≤ 0.05) reduced growth and metabolism of all the four varieties. Tolerant varieties showed more lateral roots than the sensitive ones, under Fe toxic conditions as well as higher photosynthesis rate, chlorophyll content and cell membrane stability. Strong dilution of Fe concentration in cells was identified, as one of the additional tolerance mechanisms used by CK801, whereas Suakoko 8 mainly used strong mobilisation of carbohydrates at the early stage of the stress period to anticipate metabolite shortage. Traits associated with Fe toxicity tolerance in this study could be specifically targeted in trait-based breeding programs of superior lowland rice varieties tolerant of Fe toxicity

Pengaruh Pelatihan Relaksasi Terhadap Penurunan Tingkat Kecemasan Melahirkan Anak Pertama

Tujuan penelitian untuk mengetahui pengaruh pelatihan relaksasi terhadap penurunan tingkat kecemasan melahirkan anak pertama. Hipotesis yang diajukan ada perbedaan kecemasan melahirkan anak pertama pada ibu hamil sebelum dan sesudah pelatihan relaksasi. Kecemasan melahirkan anak pertama pada ibu hamil sesudah pelatihan relaksasi lebih rendah dibandingkan sebelum pelatihan. Subjek penelitian sebanyak 10 pasien ibu hamil trisemester ke tiga, yang memeriksakan di Rumah Bersalin Aulia Boyolali. Metode pengumpulan data menggunakan skala kecemasan melahirkan anak pertama, intervensi me nggunakan pelatihan relaksasi. Data dioleh dengan teknik analisis non paramaterik wilcoxon. Hasil analisis pretest dengan posttest diperoleh nilai Z = -2,805; sig 0,005 (p< 0,01). Mean rank pretest sebesar 0,00 dan mean posttest sebesar 5,50. Hasil ini menunjukkan ada perbedaan kecemasan melahirkan anak pertama sebelum dan sesudah pelatihan. Artinya pelatihan relaksasi efektif untuk menurunkan kecemasan melahirkan anak pertama pada ibu kehamilan tri semester ketiga

Malaysian white shrimp (P. Vannamei) aquaculture: an application of stochastic frontier analysis on technical efficiency

Shrimp aquaculture is playing a vital role in Malaysian agriculture, especially its increasing contribution to economic growth. White shrimp aquaculture is not only the key player in brackish water shrimp aquaculture but also the largest contributor to Malaysian shrimp aquaculture.This study estimates technical efficiency and investigates factors affecting technical inefficiency of Malaysian white shrimp aquaculture.Stochastic frontier analysis with trans-log production model is applied in this study.Malaysian white shrimp aquaculture farmers have achieved an estimated average technical efficiency of 81.2 percent.Land ownership, shrimp seed size and seminar are the factors having significant impacts on technical inefficiency and thereby playing important roles in improving technical efficiency of this industry.This study suggests that seminar should be conducted by shrimp farming extension agents to enhance knowledge of shrimp farmers.Malaysian government should allocate lands and, provide technical and financial supports to develop this industry. Subsidy on shrimp seed should be also given to encourage shrimp farmers to embrace and adopt quality shrimp seed for their farms

Simulation of Ammonia Production using HYSYS Software

Now-a-days, Because of cost and time consuming in the design of plants chemical engineer used simulators to simulate design and operation of chemical equipment and plant,  which spares a great deal of time and cash.Today, there are many number of the simulators are refreshed and utilized in the simulation of chemical equipment and plant such as ChemCad, ProII, UniSim……..etc. Among of these simulators, Aspen Hysys is the most utilized programming in all ventures because of aiding in two noteworthy fields (design &amp; operation). Simulation of ammonia synthesis process is done on Aspen Hysys V8.8 with steady state mode making some assumptions and using hypothetical reactors ammonia. By fluctuating the distinctive parameters in this simulation environment, the impact of these parameters in the generation rate of the procedure are watched. Keywords: Ammonia, Simulation, Aspen Hysys DOI: 10.7176/CPER/62-03 Publication date: January 31st 202

Adoption of Fragrant Rice Farming: The Case of Paddy Farmers in the East Coast Malaysia

AbstractAnnually, Malaysia has to import approximately 30% of rice, including fragrant rice (Basmati and Jasmine type) to meet the shortage of domestic demand. The import of this specialty rice shows an up surging trend every year with a value of RM500 million. Mas Wangi or MRQ74 that has special characteristics and 80% similar attributes to Basmati type has been officially released in year 2005. The special characteristics such as long and slender grain shape, non- sticky and aromatic rice makes it preferred by Malaysian consumers and enabling it to tap the higher-end rice market, compared to normal white rice. The fragrant rice farming is one of the government initiatives to produce fragrant rice in large areas and needs full commitment from the farmers in non-granary areas. This study seeks to determine factors that influence new rice variety, MRQ74 adoption among paddy farmers in East Coast, Malaysia including the adoption behaviour. The study involved 28 farmers in non-granary areas in two districts; Pasir Mas and Tanah Merah, Kelantan via an in-depth interview approach. The results revealed that apart from the technology characteristics, there are other significant aspects that influence the adoption decision-making of the farmers such as extension services, capital resources, social influences, and institutional factor

Experimental verification of null steering by element positionperturbations

Null steering in an adaptive array is realized by element position perturbations. Small position perturbations are assumed, which is valid when the number of imposed nulls is small compared to the number of array elements. The null steering has been achieved for an eight-element monopole array over a ground plane. The array illumination function is used solely for pattern formation and can also be used for main beam steering. Single and double nulls are realized in the sidelobe region. The experimental results prove the validity of null steering by controlling the element position

Null steering in phased arrays by controlling the element positions

Null steering methods usually involve costly and complicated amplitude and/or phase control systems. A technique is presented for null steering based on the element position perturbations. The technique frees the phase shifters to be used solely for steering the main beam toward the direction of the desired signal. It also removes the limitations of the other techniques by independently steering the main beam and the nulls to arbitrary independent directions. This technique is also capable of obtaining sidelobe cancellation and wideband signal rejectio

On Estimating a Constant Stress Life Test Model Using Time-Censored Data from the Linear Failure Rate Distribution

In this paper, a constant stress partially accelerated life test model is considered and investigated using type-I censored data from the linear failure rate distribution. The maximum likelihood estimates (point and interval) of the distribution parameters and the acceleration factor are obtained. For accuracy reasons, the mean squared errors are calculated using different sizes of samples. For illustration, Monte Carlo simulation studies are presented.Предложена модель частично ускоренных испытаний на циклическую долговечность с постоянным напряжением с использованием данных, подвергнутых цензурированию типа I с линейным распределением скорости разрушения. Получены точечные и интервальные оценки максимального правдоподобия параметров распределения и коэффициента ускорения. С целью повышения точности прогнозов расчет среднеквадратических погрешностей осуществлялся для образцов разных размеров. Для иллюстрации работоспособности модели выполнено моделирование тестовых задач с использованием метода Монте-Карло.Запропоновано модель частково прискорених випробувань на циклічну довговічність з постійною напругою з використанням даних, які було піддано цензуруванню типу I із лінійним розподілом швидкості руйнування. Отримано точкові й інтервальні оцінки максимальної правдоподібності параметрів розподілу і коефіцієнта прискорення. Із метою підвищення точності прогнозів розрахунок середньоквадратичних похибок проводився для зразків різних розмірів. Для ілюстрації роботоздатності моделі виконано моделювання тестових задач із використанням методу Монте-Карло

Combined modal parameters-based index for damage identification in a beamlike structure: theoretical development and verification

A new index for detecting the damage severity in structural elements by combining modal parameters is proposed in this study. The index is based on the combined effect of both the natural frequencies and mode shapes when a change in stiffness of the structural element occurs. In order to demonstrate the significance and capability of this new algorithm, the magnitude of damage was calculated from a finite element model of a beam-like structure model and comparisons with previous algorithms were carried out. The new index called Combined Parameter Index (CPI) compares the factor of reduction in stiffness according to reduction in natural frequencies and also the factor of reduction in stiffness according to change in mode shape. Various damage levels starting from reduction in stiffness of 1 were adopted to validate the sensitivity of the new index to detect the damage severity at various deterioration levels. Mid-span and quarter-span damage positions were adopted to verify the capability of the new damage index to detect the damage severity at various locations. Moreover, damage in support condition was investigated in order to ascertain that the new damage index can also identify support damage cases. The results indicate that the new index has better ability and higher sensitivity to determine the severity of the damage due to stiffness changes in the element or support. In addition, the CPI exhibits sensitivity to detect lower level of damage occurring at earlier stage by having the ability to detect a damage of 1 reduction in the structural element stiffness or elastic bearing stiffness