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Sepsis is a serious medical condition characterized by bacterial infection and a subsequent massive systemic inflammatory response. In an effort to identify compounds that block lipopolysaccharide (LPS)-induced inflammation reported herein is the development of simple Lipid-A analogues that lack a disaccharide core yet still possess potent antagonistic activity against LPS. The structure of the new lead compound was developed based on predictive computational experiments. LPS antagonism by the lead compound was not straightforward, and a biphasic effect was observed suggesting a possibility of more than one binding site. An IC(50) value of 13 nM for the new compound was determined for the possible high affinity site. The combination of computational, synthetic, and biological studies revealed new structural determinants of these simplified analogues. It is expected that the acquired information will aid future design of LPS targeting glycopharmaceuticals.

Three decades of research, both in vitro and in vivo, have demonstrated the conformational heterogeneity that is displayed by the amyloid β peptide (Aβ) in Alzheimer's disease (AD). Understanding the distinct properties between Aβ conformations and how conformation may impact cellular activity remain open questions, yet still continue to provide new insights into protein misfolding and aggregation. In particular, there is interest in the group of soluble oligomeric prefibrillar Aβ species comprising lower molecular weight oligomers up to larger protofibrils. In the current study, a number of strategies were utilized to separate Aβ protofibrils and oligomers and show that the smaller Aβ oligomers have a much different conformation than Aβ protofibrils. The differences were consistent for both Aβ40 and Aβ42. Protofibrils bound thioflavin T to a greater extent than oligomers, and were highly enriched in β-sheet secondary structure. Aβ oligomers possessed a more open structure with significant solvent exposure of hydrophobic domains as determined by tryptophan fluorescence and bis-ANS binding, respectively. The protofibril-selective antibody AbSL readily discerned conformational differences between protofibrils and oligomers. The more developed structure for Aβ protofibrils ultimately proved critical for provoking the release of tumor necrosis factor α from microglial cells. The findings demonstrated a dependency on β-sheet structure for soluble Aβ aggregates to cause a microglial inflammatory response. The Aβ aggregation process yields many conformationally-varied species with different levels of β-structure and exposed hydrophobicity. The conformation elements likely determine biological activity and pathogenicity.

In the current study, the response of cv. Fortuna grown under high tunnel conditions to water deficiency and bio-stimulant application were inspected by evaluating the morphological (crown number, whole crown diameter and leaf area) and physiological (stomatal conductance and leaf water potential) parameters along with the yield. The amounts of applied irrigation water were 1.00 (control) and 0.50 times water evaporation from surface measured by a standard Class A pan. In current study, when compare to drought conditions, application of bio-stimulant resulted in the increase of crown number (25%), yield (13%), mean fruit weight (11%), leaf area (9%), stomatal conductance (8%), leaf water potential (6%), whole crown diameter (% 5) and fruit number (3%). Moreover; it could be stated that cv. Fortuna responded to water deficiency, besides stomatal closure, by reduction of leaf area, fruit number, crown number, whole crown diameter, leaf water potential (Lwp), mean fruit weight and yield. When the interactions between bio-stimulant applications and limited-watered conditions (IR 50 ) are examined in terms of their morpho-physiological responses, it has been found there are clearly abundant variation for stomatal conductance (12%), leaf area (4%), Lwp (5%) and mean fruit weight (8%). All these results show that bio-stimulant applications should be combined with optimal irrigation water, besides, obtaining information about plant morpho-physiological responses under drought conditions can contribute to improving of plant adaptations under multiple stress conditions for strawberry. © 2018, Centenary University. All rights reserved.

This study was conducted in order to compare the alternate every other furrow surge irrigation (AFO) to the every furrow surge irrigation (EFO), under Mediterranean conditions in Turkey at the Cukurova University experimental farm. The experiment was undertaken in order to determine the appropriate throughput at furrow lengths of 110 m. In general, depending on the water flow (0.87-1.16 L/s) and the duration of the irrigation application (228-272 min), there may be differences on the amount of water under the same flow rates with the use of similar forms of operating furrow application of the AFO, which was determined to be more advantageous than the application of the EFO. The application efficiencies were quite similar by 78% in the EFO and 84% in the AFO, respectively. The reason for these high efficiencies was found to be due to the lacking irrigation application concerning the time of irrigation and the rate of water flow. Significant water savings were achieved by AFO compared to the EFO technique in the field by using the furrows in turns at each irrigation operation. The average soybean yields for both two years were 252 kg/da for the EFO and 259 kg/da for the AFO application. The results of the experiment revealed that the AFO furrow irrigation technique was the appropriate surface irrigation technique for the studied area.

Lysimeters are considered the standard for evapotranspiration (ET) measurements. However, these units are often not replicated and are few in number at any given location. The Bowen ratio-energy balance (BREB) is a micrometeorological method often used to estimate ET because of its simplicity, robustness, and cost. In this paper, ET of irrigated soybean (Glycine max L.) was directly measured by weighing lysimeter and estimated by BREB method over a growing season in a semi-arid climate of eastern Mediterranean region. The study was conducted in Adana-Turkey during the summer of 2009 on a 0.12 ha area with a weighing lysimeter (2.0 × 2.0 × 2.5 m) located in the center of the field completely covered by well watered soybean where the prevailing direction of the wind and the upwind fetch was about 60 m. Cumulative evapotranspiration totals from the lysimeter and BREB methods were 354 and 405 mm, respectively. The BREB method showed a good performance for daily ET estimation when compared to values measured by lysimeter. This method, with a root mean square error (RMSE) of 0.79 mmd-1 and a 0.96 index of agreement, over-estimates lysimetric measurements by 15%. The BREB method also performs well compared with lysimetric measurements for hourly ET, but produces overestimation of 14% with RMSE of 0.128 mmh-1, and a 0.92 index of agreement. © 2010 Academic Journals.

This study was carried out to determine the crop water stress index (CWSI) for drip irrigated cotton grown on a heavy clay texture soil (Palexerollic Chromoxerert) under semi-arid climatic condition of East Mediterranean region for three years (2005 to 2007) in Adana, Turkey. Four irrigation treatments designated as full (I100) with no water stress and slight (DI70), moderate (DI50) and strong water stress (continuous stress, dry land) (DI00) were tested. The treatments of DI70 and DI50 received water amount of 70 and 50% of the control treatment and the DI00 was not irrigated except for germination water given at the beginning of the growing season. Irrigation was initiated when leaf water potential (LWP) reached to -15 bar for full (I100), -17 bar for DI70 and -20 bar for DI50 irrigation treatments. After first irrigation, all the treatments were irrigated at one week interval. The deficit irrigation affected, the irrigation water use, seed cotton yield, dry matter and some yield components such as plant height and number of boll per plant of cotton. Average values of water use, seed cotton yield, dry matter and water use efficiency of full irrigated cotton were 578 mm, 3.28 tha-1, 13.44 tha-1 and 0.59 kgm-3, respectively. CWSI values were calculated from the measurements of canopy temperatures by infrared thermometer (IRT), ambient air temperatures and vapor pressure deficit values for all the irrigated treatments. A non-water stressed baseline (lower baseline) equation for cotton was developed using canopy temperature measured from full irrigated plots as, Tc −Ta = −1.7543VPD +1.56; R2=0.5327 and the non-transpiring baseline (upper baseline) equation was built using canopy temperature data taken from continuous stress plots as, Tc −Ta = −0.0217VPD + 3.2191. The trends in CWSI values were consistent with the varying soil water content due to the deficit irrigation programs. The relationships between mean CWSI and plant parameters considered in this study were linear except for irrigation water amount. Both dry matter and seed cotton yield decreased with increased soil water deficit. Seed cotton yield (SY) and seasonal mean CWSI values relationship were obtained as, SY = −2.3552CWSI + 3.5657 ; R2=0.499. This relationship can be used to predict the seed cotton yield. The results suggest that the cotton crop for this particular climate and soil conditions, should be irrigated when CWSI approaches 0.36. The CWSI approach, according to results of this study, can be accepted as a useful tool to schedule irrigations for cotton.Key words: Crop water stress index (CWSI), evapotranspiration, cotton, drip irrigation.

This study examines the effects of different irrigation regimes on yield and water use of pepper irrigated by a drip system under field conditions during the 2004 growing season at the Soil and Water Resources Research Institute in Tarsus, Turkey under Mediterranean climatic conditions. The field trials consisted of three irrigation intervals (IF1:20±2, IF2:40±2 and IF3:60±2 mm of cumulative pan evaporation) and evaluated by three irrigation levels (DI1=0.50, DI2=0.75 and DI3=1.00). Both the irrigation levels (DI) and intervals (IF) had significantly different effects on pepper yields. The maximum and minimum yields were obtained from the IF1DI3 and IF3DI1 treatment plots as 35920 and 21390 kg ha-1, respectively. The yields and yield components decreased as irrigation levels decreased for each irrigation interval. However, the larger irrigation interval (IF3) resulted in lower yields with all irrigation levels. Pepper seasonal evapotranspiration varied from a low 327 mm in the more stressfull treatment (IF3DI1) to a high 517 mm in the well irrigated control (IF1DI3). Significant linear relations were found between the pepper yield and the total water use for each irrigation interval. Irrigation intervals resulted in similar water use in the treatments with the same irrigation level. Water use efficiency (WUE) and irrigation water use efficiency (IWUE) values were significantly influenced by the irrigation intervals and levels. WUE ranged from 6.0 kg m-3 in IF3DI2 to 7.8 kg m-3 in the IF1DI1. The maximum IWUE was observed in IF1DI1, and the minimum IWUE was in IF3DI3 treatment. Both irrigation levels and frequencies had significantly different effects on quality parameters such as the first and second quality yield, number of fruit, mean fruit weight, pepper length and width, as well as plant height at harvest. In conclusion, the IF1DI3 irrigation regime is recommended for field grown pepper in order to attain higher yields with improved quality. Economic evaluation revealed that full irrigation treatment (IF1DI3) generated the highest net income. However, under water scarcity conditions, IF1DI2 treatment can provide an acceptable net income.Key words: Pepper, deficit irrigation, water use efficiency, yield response factor, economic evaluation.