Effect of tillage and residue retention on maize productivity

In Bangladesh, maize is generally sown after extensive tilth and minimum residue retention. Conservation agriculture (CA) systems reduce the input costs, machinery use, CO2 emissions; and improve soil health (Raper et al., 1994). Crop residues are known to affect soil physical properties (Hulugalle et al., 1986), availability of nutrients (Wade and Sanchez, 1983; Asghar et al., 2006) and soil biological activity (Tian et al., 1993). Crop residue retention has been suggested to improve overall soil fertility and to support sustainable crop production. Crop residue retention under no tillage system reduce soil erosion, increase soil organic matter (SOM), and reduce requirement of labour and fuel under cereal grain and row crop culture (Salinas-Garcia et al., 1997). Kumar and Goh (2000) reported that incorporation of crop residues is essential for sustaining soil productivity through replenishing SOM that not only a key indicator of soil quality, but it also supplies essential nutrients upon mineralization (N, P, and S) and improves soil physical, chemical, and biological properties (Kumar et al., 2001). In our country, the crop residue is used mostly for cattle feed (Saadullah et al., 1991), fuel for stove and some cases burning. It is essential to estimate the amount of crop residue that should be retained in field to get the benefits. Therefore, the present research investigated to find out the minimum tillage with residue retention could be an effective element for maize production

Evaluation of two concepts of fertilization for wheat in a calcareous soil of Bangladesh

Two popular concepts of soil fertilization, basic cation saturation ratio (BCSR) and sufficiency level of available nutrients (SLAN), were tested on a calcareous soil (Aeric haplaquept) during 1995-1996 at the Bangladesh Rice Research Institute (BRRI) Regional Station Rajshahi using wheat as a test crop. According to BCSR concept the soil was deficient in potassium (K) and according to SLAN concept it was deficient in phosphorus (P), respectively. Potassium dose of 120 kg ha-1 [to attain 2% saturation of total cation exchange capacity (CEC) according to BCSR] along with other two doses (0 and 60 kg K ha-1) and P dose of 50 kg ha-1 (to attain available P at sufficiency level) along with other two doses (0 and 100 kg P ha-1) were compared in a randomized complete block design. The application of 50 kg P ha-1 significantly increased plant height, spikes m-2, grains per spike, grain and straw yields of wheat over 0 kg P ha-1 with or without K but increasing P dose from 50 to 100 kg P ha-1 did not give additional yields. The agronomic parameters and yields were not affected significantly by K application. Similar results were also observed in nutrient content and nutrient uptake. Thus, SLAN concept appeared as an effective tool for fertilizer recommendation for the calcareous soil while BCSR gave no apparent result there

Yield and phosphorus efficiency of some lowland rice varieties at different levels of soil‐available phosphorus

A field experiment was conducted on an Aeric Haplaquept soil to study the effect of phosphorus (P) deficiency in soil on the P nutrition and yield of five modern varieties of rice, viz., Purbachi, BR1, BR3, BR14, and BR29, popular with the rice farmers of Bangladesh. Soil-available P in the different plots of the experimental field varied widely, from 2.8 to 16.4 ppm. This plot to plot variation in soil-available P content resulted from differences in the total amounts (0 to 480 kg ha -1) of P the plots had received over a period of 8 years in a long-term P fertilizer trial conducted previously in the same field. Phosphorus deficiency in soil drastically reduced the grain yield of all the rice varieties. In severely P deficient plots, where soil-available P was around 3 ppm, the yield was less than 1 ton ha -1 while in plots containing an adequate P level, i.e., >6 ppm, the yield was more than 4 t ha -1. Rice yield increased linearly with an increase in soil P content up to 6 ppm, and the highest grain yield for any variety, obtained at 6-7 ppm of soil-available P leveled off at this point. Soil P deficiency not only decreased rice yield severely but also decreased P content in straw and grain drastically. However, differences among rice varieties were noted in P nutrition, particularly at low soil P levels. The rice varieties differed markedly also in respect of internal P efficiency. The BR29 showed the highest internal P efficiency both at low and high soil P levels. In all the rice varieties, internal P efficiency decreased with an increase in soil P levels

Differential Transcriptional Regulation of meis1 by Gfi1b and Its Co-Factors LSD1 and CoREST

Gfi1b (growth factor independence 1b) is a zinc finger transcription factor essential for development of the erythroid and megakaryocytic lineages. To elucidate the mechanism underlying Gfi1b function, potential downstream transcriptional targets were identified by chromatin immunoprecipitation and expression profiling approaches. The combination of these approaches revealed the oncogene meis1, which encodes a homeobox protein, as a direct and prominent target of Gfi1b. Examination of the meis1 promoter sequence revealed multiple Gfi1/1b consensus binding motifs. Distinct regions of the promoter were occupied by Gfi1b and its cofactors LSD1 and CoREST/Rcor1, in erythroid cells but not in the closely related megakaryocyte lineage. Accordingly, Meis1 was significantly upregulated in LSD1 inhibited erythroid cells, but not in megakaryocytes. This lineage specific upregulation in Meis1 expression was accompanied by a parallel increase in di-methyl histone3 lysine4 levels in the Meis1 promoter in LSD1 inhibited, erythroid cells. Meis1 was also substantially upregulated in gfi1b2/2 fetal liver cells along with its transcriptional partners Pbx1 and several Hox messages. Elevated Meis1 message levels persisted in gfi1b mutant fetal liver cells differentiated along the erythroid lineage, relative to wild type. However, cells differentiated along the megakaryocytic lineage, exhibited no difference in Meis1 levels between controls and mutants. Transfection experiments further demonstrated specific repression of meis1 promoter driven reporters by wild type Gfi1b but neither by a SNAG domain mutant nor by a DNA binding deficient one, thus confirming direct functional regulation of this promoter by the Gfi1b transcriptional complex. Overall, our results demonstrate direct yet differential regulation of meis1 transcription by Gfi1b in distinct hematopoietic lineages thus revealing it to be a common, albeit lineage specific, target of both Gfi1b and its paralog Gfi1

Phosphorus sorption and saturation in the Ganges tidal floodplain soils of Bangladesh

The soils developed from the Ganges sediments in the coastal area of Bangladesh and India extend several thousand hectares and important from the view point of rice cultivation. Phosphorus, one of the important environmental and agricultural element, retention behavior of the Ganges floodplain soils is poorly reported. The objective of this study was to determine maximum phosphorus adsorption capacity (MPAC) and to develop Psat for 13 Ganges Tidal Floodplain soils of Bangladesh. The MPAC value and Psat based on Mehlich-3 extractions were determined. The conventional adsorption equations, such as the Langmuir, Freudlich and Temkin equations were used to describe the P sorption of the studied soils. The MPAC value varied from 1250 to 2000 mg/kg and correlated with EC (r = 0.59, p<0.05) and CEC (r = -0.74, P<0.01). The sorption capacity of the tested soils ranged from 511 to 545 mg/kg and the calculated energy of adsorption of the soils varied from 0.192 to 1.00 μg/mL and it was a positively correlated with clay (r=0.7, p<0.01) and CEC (r = 0.63, p<0.05) but negatively with silt (r= -0.80, p<0.01), pH (H2O) (r=-0.60, p<0.05) and with MPAC (r=-0.59, p<0.05) values. Phosphorus saturation indices of the studied sample demonstrated a far below the threshold critical limit of 25%

Recent Advancement in Solar-Driven Interfacial Steam Generation for Desalination : A State-of-the-Art Review

Solar energy is one of the most efficient origins of energy for a wide range of environmentally beneficial purposes. Water desalination by steam generation with the help of solar energy is not only an economical and straightforward approach, but it also utilizes free energy sources to solve the problem of increasing freshwater scarcity. Solar water evaporation is an essential component of the low-energy method for generating fresh water, which is required for economic development and human health. Freshwater productivity determines how effectively the system captures incoming solar energy and transforms it into usable heat. Effective water distillation has recently gained a lot of attention. The photothermal conversion process is built on the performance of the evaporator. This review thoroughly examines the most recent developments in photothermal materials, structure design, and engineering strategies, including design principles for highly efficient photothermal conversion, thermal management, water transport phenomena, salt rejection behavior, and improved evaporation rate. The prospective applications of this technique in saline water desalination, waste water purification, and energy generation are highlighted. Furthermore, the most recent scientific advancements are utilized to demonstrate the potential, prospects, and challenges of solar-driven evaporation in energy conversion

Progress in interfacial solar steam generation using low-dimensional and biomass-derived materials

The pressing concern of escalating water scarcity has spurred the creation of advanced technologies, such as interfacial solar steam generation (ISSG), to tackle the challenge. ISSG employs solar energy for efficient water desalination and purification. This comprehensive review delves into various aspects of ISSG, primarily focusing on elucidating its mechanisms, optimizing substrate materials, implementing thermal management strategies, and exploring applications. The study dissects the intricate mechanism of ISSG, highlighting photothermal behaviors across different materials, including the significant role of nanoparticles in vapor generation. The impact of substrate composition and shape on solar evaporation efficiency is investigated, with multi-surface evaporators considered for environmental energy harnessing. To enhance performance, thermal management strategies, including innovative water transport paths for improved heat distribution, are assessed. Addressing key challenges like salt accumulation, biofouling, corrosion, and oil fouling, the review offers insights for issue mitigation. Practically, ISSG is spotlighted for its role in seawater desalination, wastewater treatment (e.g., dye and heavy metal removal), oil-water separation, and sterilization, extending its relevance across industries and healthcare. By comprehensively examining ISSG's mechanisms, substrate considerations, thermal strategies, and applications, this review advances its implementation as a transformative solution for global water challenges

Position and sequence conservation in Amniota of polymorphic enhancer HS1.2 within the palindrome of IgH 3'Regulatory Region

<p>Abstract</p> <p>Background</p> <p>The Immunoglobulin heavy chain (IgH) 3' Regulatory Region (3'RR), located at the 3' of the constant alpha gene, plays a crucial role in immunoglobulin production. In humans, there are 2 copies of the 3'RR, each composed of 4 main elements: 3 enhancers and a 20 bp tandem repeat. The single mouse 3'RR differs from the two human ones for the presence of 4 more regulative elements with the double copy of one enhancer at the border of a palindromic region.</p> <p>Results</p> <p>We compared the 3'RR organization in genomes of vertebrates to depict the evolutionary history of the region and highlight its shared features. We found that in the 8 species in which the whole region was included in a fully assembled contig (mouse, rat, dog, rabbit, panda, orangutan, chimpanzee, and human), the shared elements showed synteny and a highly conserved sequence, thus suggesting a strong evolutionary constraint. In these species, the wide 3'RR (~30 kb in human) bears a large palindromic sequence, consisting in two ~3 kb complementary branches spaced by a ~3 kb sequence always including the HS1.2 enhancer. In mouse and rat, HS3 is involved by the palindrome so that one copy of the enhancer is present on each side. A second relevant feature of our present work concerns human polymorphism of the HS1.2 enhancer, associated to immune diseases in our species. We detected a similar polymorphism in all the studied Catarrhini (a primate parvorder). The polymorphism consists of multiple copies of a 40 bp element up to 12 in chimpanzees, 8 in baboons, 6 in macaque, 5 in gibbons, 4 in humans and orangutan, separated by stretches of Cytosine. We show specific binding of this element to nuclear factors.</p> <p>Conclusions</p> <p>The nucleotide sequence of the palindrome is not conserved among evolutionary distant species, suggesting pressures for the maintenance of two self-matching regions driving a three-dimensional structure despite of the inter-specific divergence at sequence level. The information about the conservation of the palindromic structure and the settling in primates of the polymorphic feature of HS1.2 show the relevance of these structures in the control and modulation of the Ig production through the formation of possible three-dimensional structures.</p

Maximum parsimony analysis of gene expression profiles permits the reconstruction of developmental cell lineage trees

AbstractSpatiotemporal control of gene expression lies at the heart of generating several hundred distinct cell types required for the development of higher order animals. Different cell types within complex organs are often characterised by means of genome-wide gene expression profiling, but analogous information for early developmental as well as adult stem and progenitor cells is largely missing because their identity is commonly unknown or they are present in prohibitively small numbers. Here we show that maximum parsimony approaches previously used to reconstruct evolutionary trees from gene content of extant species can be adapted to reconstruct cellular hierarchies both during development and steady state homeostasis of complex mammalian tissues. Using haematopoiesis as a model, we show that developmental trees reconstructed from expression profiles of mature cells are not only consistent with current experimentally validated trees but also have predictive value in determining progenitor cell specific transcriptional programmes and lineage determining transcription factors. Subsequent analysis across diverse developmental systems such as neuronal development and endoderm organogenesis demonstrated that maximum parsimony-based reconstruction of developmental trees represents a widely applicable approach to infer developmental pathways as well as the transcriptional control mechanisms underlying cell fate specification

rGO coated cotton fabric and thermoelectric module arrays for efficient solar desalination and electricity generation

One promising solution to the freshwater crisis is solar-driven interfacial evaporation-based desalination. However, an alternate strategy is needed to address both water and energy shortages in parallel. Additionally, the disposal of desalination brine necessitates specific consideration while designing a sustainable solar interfacial desalination system. Herein, we demonstrate a single system that utilizes incident solar irradiance to produce interfacial steam using reduced graphene oxide (rGO) coated cotton fabric (CF) to desalinate seawater with an evaporation efficiency of 86.98%. The high thermal conductivity and excellent optical absorption of rGO contribute to the absorption of a broad solar spectrum. The system also produces 339.26 mW of electricity simultaneously by deploying commercially available thermoelectric generator (TEG) modules that use the squandered heat, increasing the overall system efficiency by 7.3%. The use of a custom-made power electronics module ensures operating at the maximum power point which has also been verified by computer simulation. Finally, hydrogen gas with zero carbon emission is produced by electrolyzing the seawater utilizing the electricity generated by the TEG module using solar-induced heat at a rate of 0.52 mmol h −1. Converting brine into hydrogen and oxygen gas by electrolysis demonstrates a potential in situ approach for desalination waste remediation