Economic comparison of tillage and planting operations in three tillage systems

 To study the economy of tillage operations and present suitable systems for land preparation and planting, costs of execution of three different tillage operations in irrigated wheat crop were compared for three successive years.  The three systems include: conventional or maximum tillage (Max-till), reduced tillage (Red-till) using multitask machine, and using direct planting machinery to represent the no-tillage case (No-till).  Costs were composed of rental cost of tractor, the used implements, multitask machine and direct planting machine.  For each case, data were compared and analyzed in randomized block design.  The variance of wheat yield in the three tillage systems was significant at the 1% level.  Total costs per hectare were 109 and 78 and 46 Dollars for Max-till, Red-till and the No-till case, respectively.  Since, the test area under cultivation was part of a 200 hectare farm, crop protection and harvesting operations were carried out alike in the whole farm.  Accordingly, operations costs were estimated as 445 Dollars ha-1 tare.  Average yields of 7.85, 7.68, 5.2 t ha-1 were obtained, respectively, for Max-till, Red-till and No-till systems.  Since, the price per kg of wheat was equal to 0.36 Dollars ha-1, the profits of the harvest was equal to 2,271 Dollars ha-1 for the Max-till, 2,242 Dollars ha-1 for Red-till and 1,384 Dollars ha-1 for the No-till system.  In tillage and planting operations, usage of the reduce tillage system is offered as an alternative to the conventional tillage and no-till systems.  The Red-till system reduces fuel consumption, operation time, soil compaction due to decrease in the number of tractor trips, which leads to reduced production costs.  In addition, less investment in purchasing implements and preparation of the soil, which breaks the soil cohesion, are achieved with the reduced tillage system.   Keywords: costs of production, field performance, Max-till, Multitask machine, no-till, red-till, soil compaction

Bioaccumulation of heavy metals Cu, Zn, and Hg in muscles and liver of the stellate sturgeon (Acipenser stellatus) in the Caspian Sea and their correlation with growth parameters

Bioaccumulation of Cu, Zn, Hg in muscles and liver tissues of stellate sturgeon (Acipenser stellatus) from the southern Caspian Sea was measured. Effects of condition factor (CF), age and hepatosomatic index (HSI) on metal accumulation were also determined. Some 40 stellate sturgeons were collected using gill nets in winter and spring 2007-2008 from the southern shores of the Caspian Sea. Total (TL) and fork (FL) length and weight of all specimens were measured. Cross sections of first ray of pectoral fins were used for age determination. Muscle and liver samples were taken and transported to the laboratory in ice packs and kept in -20 °C prior to analyses. In the laboratory samples were oven dried, digested with HClO3 and HNO3 and diluted with dionized water to 50cc to measure Cu, Zn, and Hg concentration with a flame spectrophotometer. Sequence of metals in Acipenser stellatus was Zn>Hg> Cu in muscle tissues and Zn>Cu>Hg in liver samples. Concentration of Zn was slightly in correlation with age (R= 0.3). A negative correlation was observed between Zn concentrations with condition factor (R = -0.3). Zn concentrations were negatively correlated in muscle tissues (R = -0.3). The results were compared to international standards proposed by MAAF, EEC and NHMRC. Our study showed that accumulation of heavy metals in sturgeon tissues was influenced by concentration of metals in sediment and the physiological state of fish

Concentration of heavy and toxic metals Cu, Zn, Cd, Pb and Hg in liver and muscles of Rutilus frisii kutum during spawning season with respect to growth parameters

Concentration of heavy and toxic metals Cu, Zn, Cd, Pb and Hg were determined in liver and muscles of Rutilus frisii kutum and their relationships with growth parameters (length, age, condition factor) and hepatosomatic index were examined. Thirty-six fish samples were collected from February through March 2009 caught by beach seine in the southwest parts of the Caspian Sea. Atomic absorption and Hg determined concentrations of Cd, Pb, Zn and Cu by vapor method. Cadmium was recorded only in liver samples. Range of other metals in muscle tissue were ND-0.591, 0.001-0.013, 11-26 and 0.729-7.261 µg/g dw for Pb, Hg, Zn and Cu respectively. Highest levels of Pb, Zn, and Cu were recorded in muscles Hg and Cd in liver samples. Growth parameters showed a significant relationship with Zn and Cd concentrations in liver samples and only Zn concentrations in muscle samples. There was a positive significant correlation between concentration of Cd in liver and physiological indices (p<0.05). Although higher concentration of Pb was recorded in this study in comparison to previous studies, based on Provisional Tolerable Weekly and daily Intake of fish for human health, kutum is considered safe for human consumption. Considering the results of this study it seems reproductive status of the fish influences heavy metals concentration in liver and muscles of kutum and therefore concentrations of some metals such as Zn and Cu in liver samples may not be a reliable bioindicator for environmental pollution

Disparity of Cytochrome Utilization in Anodic and Cathodic Extracellular Electron Transfer Pathways of Geobacter sulfurreducens Biofilms.

Extracellular electron transfer (EET) in microorganisms is prevalent in nature and has been utilized in functional bioelectrochemical systems. EET of Geobacter sulfurreducens has been extensively studied and has been revealed to be facilitated through c-type cytochromes, which mediate charge between the electrode and G. sulfurreducens in anodic mode. However, the EET pathway of cathodic conversion of fumarate to succinate is still under debate. Here, we apply a variety of analytical methods, including electrochemistry, UV-vis absorption and resonance Raman spectroscopy, quartz crystal microbalance with dissipation, and electron microscopy, to understand the involvement of cytochromes and other possible electron-mediating species in the switching between anodic and cathodic reaction modes. By switching the applied bias for a G. sulfurreducens biofilm coupled to investigating the quantity and function of cytochromes, as well as the emergence of Fe-containing particles on the cell membrane, we provide evidence of a diminished role of cytochromes in cathodic EET. This work sheds light on the mechanisms of G. sulfurreducens biofilm growth and suggests the possible existence of a nonheme, iron-involving EET process in cathodic mode.N.K. was supported by a Royal Society Newton International Fellowship, NF160054. E.R., X.F. and N.H. acknowledge the European Research Council (ERC) Consolidator Grant “MatEnSAP” (682833). S. K. was supported by a Marie Skłodowska-Curie Fellowship (EMES, 744317). K. H. Ly acknowledges the Open Topic Postdoc Programme of the Technische Universität Dresden and the Marie Sklodowska Curie IF, GAN 701192. The TEM was funded through the EPSRC underpinning multi-user equipment call (EP/P030467/1

Disparity of Cytochrome Utilization in Anodic and Cathodic Extracellular Electron Transfer Pathways of Geobacter sulfurreducens Biofilms.

Extracellular electron transfer (EET) in microorganisms is prevalent in nature and has been utilized in functional bioelectrochemical systems. EET of Geobacter sulfurreducens has been extensively studied and has been revealed to be facilitated through c-type cytochromes, which mediate charge between the electrode and G. sulfurreducens in anodic mode. However, the EET pathway of cathodic conversion of fumarate to succinate is still under debate. Here, we apply a variety of analytical methods, including electrochemistry, UV-vis absorption and resonance Raman spectroscopy, quartz crystal microbalance with dissipation, and electron microscopy, to understand the involvement of cytochromes and other possible electron-mediating species in the switching between anodic and cathodic reaction modes. By switching the applied bias for a G. sulfurreducens biofilm coupled to investigating the quantity and function of cytochromes, as well as the emergence of Fe-containing particles on the cell membrane, we provide evidence of a diminished role of cytochromes in cathodic EET. This work sheds light on the mechanisms of G. sulfurreducens biofilm growth and suggests the possible existence of a nonheme, iron-involving EET process in cathodic mode.N.K. was supported by a Royal Society Newton International Fellowship, NF160054. E.R., X.F. and N.H. acknowledge the European Research Council (ERC) Consolidator Grant “MatEnSAP” (682833). S. K. was supported by a Marie Skłodowska-Curie Fellowship (EMES, 744317). K. H. Ly acknowledges the Open Topic Postdoc Programme of the Technische Universität Dresden and the Marie Sklodowska Curie IF, GAN 701192. The TEM was funded through the EPSRC underpinning multi-user equipment call (EP/P030467/1

Molecular investigation of methicillin-resistant staphylococcus aureus isolates from blood: USA600 emerges as the major type

Introduction: The widespread emergence of methicillin-resistant Staphylococcus aureus is turning into a real worry in public health. The goals of the present study were to identify resistance and virulence encoding genes and molecular characteristics of methicillin-resistant S. aureus bloodstream isolates. Methodology: A cross-sectional study was conducted on 84 S. aureus bloodstream isolates during a 10-month period. To evaluate antibiotic susceptibility of the isolates, we used Kirby-Bauer disk diffusion method. In addition, the prevalence of antimicrobial resistance and toxins genes was assessed using polymerase chain reaction. Isolates were typed according to polymorphisms seven housekeeping genes by MLST. Results: All the isolates were resistant to methicillin. The most prevalent resistance gene was mecA gene (100) followed by tetM (57.1), aac (6�)-Ie/aph (2�) (53.6), ant (4�)-Ia (46.4), ermA (45.2), msrA (35.7), msrB (33.3), aph (3�)-IIIa (33.3), ermB (31), ermC (16.7), and mupA (14.3) genes. The presence of toxin encoding genes tst, pvl, eta, and etb were detected in 25, 14.3, 3.6 and 3.6, respectively. The isolates were classified into five different sequence types: ST45 (29.8), ST239 (27.4), ST858 (21.4), ST22 (17.8), and ST59 (3.6). All the high-level mupirocin-resistant (HLMUPR) strains belonged to ST239, while the low-level mupirocin resistant (LLMUPR) strains belonged to ST22 (13) and ST239 (6). Conclusions: To the best of our knowledge, the present study is the first report of ST59 in MRSA bloodstream isolates in Iran. Our data demonstrated the need for thorough epidemiological monitoring to detect emergence and dissemination of MDR-MRSA types in our hospitals. © 2018 Goudarzi et al

Molecular investigation of methicillin-resistant staphylococcus aureus isolates from blood: USA600 emerges as the major type

Introduction: The widespread emergence of methicillin-resistant Staphylococcus aureus is turning into a real worry in public health. The goals of the present study were to identify resistance and virulence encoding genes and molecular characteristics of methicillin-resistant S. aureus bloodstream isolates. Methodology: A cross-sectional study was conducted on 84 S. aureus bloodstream isolates during a 10-month period. To evaluate antibiotic susceptibility of the isolates, we used Kirby-Bauer disk diffusion method. In addition, the prevalence of antimicrobial resistance and toxins genes was assessed using polymerase chain reaction. Isolates were typed according to polymorphisms seven housekeeping genes by MLST. Results: All the isolates were resistant to methicillin. The most prevalent resistance gene was mecA gene (100) followed by tetM (57.1), aac (6�)-Ie/aph (2�) (53.6), ant (4�)-Ia (46.4), ermA (45.2), msrA (35.7), msrB (33.3), aph (3�)-IIIa (33.3), ermB (31), ermC (16.7), and mupA (14.3) genes. The presence of toxin encoding genes tst, pvl, eta, and etb were detected in 25, 14.3, 3.6 and 3.6, respectively. The isolates were classified into five different sequence types: ST45 (29.8), ST239 (27.4), ST858 (21.4), ST22 (17.8), and ST59 (3.6). All the high-level mupirocin-resistant (HLMUPR) strains belonged to ST239, while the low-level mupirocin resistant (LLMUPR) strains belonged to ST22 (13) and ST239 (6). Conclusions: To the best of our knowledge, the present study is the first report of ST59 in MRSA bloodstream isolates in Iran. Our data demonstrated the need for thorough epidemiological monitoring to detect emergence and dissemination of MDR-MRSA types in our hospitals. © 2018 Goudarzi et al

Experimental assessment of the histopathological effects of water-soluble fraction of crude oil on gill tissue of juvenile Rutilus frisii kutum

The toxic effects of water soluble fraction (WSF) of crude oil on the gills of juvenile kutum roach, Rutilus frisii kutum, were investigated. The juvenile (1-2g) kutum roach were collected in summer 2008 from the Kolmeh Hatchery Center, Golestan province, and acclimatized to laboratory conditions through keeping them in a 300 liter tank with de- chlorinated water for a minimum of 8 days. Six different types of WSF concentrations were made to obtain LC5096h including 27, 29.25, 31.5, 33.75, 36 and 38.25ppm. Then, 10 fingerlings of R. frisii kutum were exposed to the WSF concentrations, for 96 hours. Considering mortality rate of the juveniles in 96 hours and using Probit value statistical analysis, LC5096h was obtained at 33.95ppm. Two different concentrations (0.1 LC50 and LC50) of WSF were prepared for further assessments and after 24 and 96h of exposure, 3 individual fish were collected from each aquarium for histopathological studies. The gill sections with 3 micron thickness were prepared, stained using H & E, and examined by light microscope. General damages after observation included: Epithelial lifting, congestion in filament and lamellae, clubbing, fusion, hypertrophy of epithelial cells of lamellae, different levels of hyperplasia between lamella and aneurysms. Pathological studies showed that the WSF of crude oil causes serious damage in gills of juvenile R. frisii kutum, leads to malfunction of this organ which will harm homeostasis of the fish