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371.
Misbah SultanKhalid Mahmood Zia Haq Nawaz BhattiTahir Jamil Rizwan HussainMohammad Zuber 《Carbohydrate polymers》2012,87(1):397-404
Polyurethane (PU) prepolymers were prepared by using two different diisocyanates i.e., toluene-2,4-diisocyanate (TDI) and or isophorone diisocyanate (IPDI), and poly (2-methyl-1,3-propylene glutarate), hydroxyl terminated group. PU prepolymer was reacted with 2-hydroxyethylacrylate (HEA) to form vinyl terminated PU prepolymer. Vinyl terminated PU prepolymers were further copolymerized with butyl acrylates (BuA) by emulsion process. The structure of proposed PUACs samples was confirmed by FT-IR, and their physicochemical properties were studied determining solid contents (%), emulsion stability and its appearance, tackiness and film appearance. Their acids and base chemical resistance was also studied and discussed. The synthesized PUACs samples were applied using dip-padding techniques on mill un-desized poly-cotton plain weave fabrics. The results emphasis that PUACs based on toluene-2,4-diisocyanate (TDI) have shown excellent performance against physical and chemical resistance as compared to isophorone diisocyanate (IPDI) based PUACs, however vice versa results were found in some studies. 相似文献
372.
This study examined the ability of duckweed (Lemna minor) to remove soluble lead from water. The duckweed was obtained from the Devils Lake wastewater treatment plant in North Dakota. The viable aquatic plants were exposed to a single dose of lead (from Pb(NO3)2) at a concentration of 5.0 mg/l for a time period of 21 days. Lead concentrations were measured in the water daily and in the biomass at the conclusion of the experiment. All measurements were done in triplicate and performed in accordance with standard methods. These data were used to calculate the removal efficiency with respect to time, and to provide the necessary empirical constants to model the removal behavior. Viable biomass removed 85–90% of the lead, viable duckweed previously exposed to lead removed 70–80% of the lead, non-viable biomass (control group) removed 60–75% of the lead, and there was no removal in the ‘no-biomass' control group. Based on these results we conclude that the viable biomass is effective in removing lead present at sub-lethal levels. 相似文献
373.
Ilahi Nikhat Degen A. Allan Bahadur Ali Haq Abdul Wang Wenyin Kang Shichang Sajjad Wasim Shang Zhanhuan 《International microbiology》2023,26(2):309-325
International Microbiology - Recently, a supraglacial lake formed as a result of a glacial lake outburst flood (GLOF) in the Dook Pal Glacier. Lake debris and meltwater samples were collected from... 相似文献
374.
Edwin R. van den Heuvel Lauren E. Griffith Nazmul Sohel Isabel Fortier Graciela Muniz-Terrera Parminder Raina 《Biometrical journal. Biometrische Zeitschrift》2020,62(1):34-52
Combining data from different studies has a long tradition within the scientific community. It requires that the same information is collected from each study to be able to pool individual data. When studies have implemented different methods or used different instruments (e.g., questionnaires) for measuring the same characteristics or constructs, the observed variables need to be harmonized in some way to obtain equivalent content information across studies. This paper formulates the main concepts for harmonizing test scores from different observational studies in terms of latent variable models. The concepts are formulated in terms of calibration, invariance, and exchangeability. Although similar ideas are present in measurement reliability and test equating, harmonization is different from measurement invariance and generalizes test equating. In addition, if a test score needs to be transformed to another test score, harmonization of variables is only possible under specific conditions. Observed test scores that connect all of the different studies, are necessary to be able to test the underlying assumptions of harmonization. The concepts of harmonization are illustrated on multiple memory test scores from three different Canadian studies. 相似文献
375.
Mutation breeders often estimate an irradiation dose which causes a specified reduction in growth of a biological material. In this paper, we estimate the growth reduction dose (GRD) and its confidence interval, when the dose-response relationship is of a general polynomial form. We make a realistic assumption that the response at the control dose is a random variable. We compare the estimates, standard error and confidence intervals of GRD with those obtained under a situation where response at control dose is a known constant. We illustrate the procedure with data on the effect of gamma irradiation and Ethylmethane sulphate on shoot lengths of chickpea genotypes. 相似文献
376.
In an African female infant with exstrophy who was a candidate for complete reconstruction of the urinary tract, pelvis, and abdominal wall, the treatment program was simplified by performing iliac osteotomies at the same time as the other repairs, using a single transverse lumbosacral incision for access. A series of 3 wire loops held the symphysis in apposition. A plaster spica, followed by a plaster girdle, minimized the tension on the pubic wires. We believe that we obtained, by this method, superior strength and a better appearance of the abdominal wall and perineum. 相似文献
377.
Ul Haq Zaheer Uddin Reaz Wai Lam Kok Wadood Abdul Lajis Nordin Haji 《Journal of molecular modeling》2011,17(5):1149-1161
Structure-based 3D-QSAR approaches (CoMFA and CoMSIA) were applied to understand the structural requirements of the Cyclin-dependent
kinase 5/p25 inhibitors. Cyclin-dependent kinase 5 (CDK5) is believed to play an important role in the development of the
central nervous system during the process of mammalian embryogenesis. Genetic algorithm based docking program (GOLD) was successfully
utilized to orient the compounds inside the binding pocket of the CDK5/p25 structure. The adapted alignment method with the
suitable parameters resulted in a reliable model. Furthermore, the final model was robust enough to forecast the activities
of test compounds, satisfactorily. The contour maps were produced around the functional groups to understand the SAR requirements.
Moreover, we also investigate the structural attributes of the inhibitors which make them selective toward CDK5/p25 over its
close counterpart, i.e., CDK2. The study could be helpful to rationalize the new compounds with better inhibition and selectivity
profiles against CDK5/p25. 相似文献
378.
Marijana Samardzija Andrea Corna Raquel Gomez-Sintes Mohamed Ali Jarboui Angela Armento Jerome E. Roger Eleni Petridou Wadood Haq Francois Paquet-Durand Eberhart Zrenner Pedro de la Villa Günther Zeck Christian Grimm Patricia Boya Marius Ueffing Dragana Trifunovi 《Cell death and differentiation》2021,28(4):1317
Cone photoreceptor cell death in inherited retinal diseases, such as Retinitis Pigmentosa (RP), leads to the loss of high acuity and color vision and, ultimately to blindness. In RP, a vast number of mutations perturb the structure and function of rod photoreceptors, while cones remain initially unaffected. Extensive rod loss in advanced stages of the disease triggers cone death by a mechanism that is still largely unknown. Here, we show that secondary cone cell death in animal models for RP is associated with increased activity of histone deacetylates (HDACs). A single intravitreal injection of an HDAC inhibitor at late stages of the disease, when the majority of rods have already degenerated, was sufficient to delay cone death and support long-term cone survival in two mouse models for RP, affected by mutations in the phosphodiesterase 6b gene. Moreover, the surviving cones remained light-sensitive, leading to an improvement in visual function. RNA-seq analysis of protected cones demonstrated that HDAC inhibition initiated multi-level protection via regulation of different pro-survival pathways, including MAPK, PI3K-Akt, and autophagy. This study suggests a unique opportunity for targeted pharmacological protection of secondary dying cones by HDAC inhibition and creates hope to maintain vision in RP patients even in advanced disease stages.Subject terms: Neuroscience, Neurological disorders 相似文献
379.
Optimizing methyl‐eugenol aromatherapy to maximize posttreatment effects to enhance mating competitiveness of male Bactrocera carambolae (Diptera: Tephritidae) 下载免费PDF全文
Ihsan ul Haq Marc J.B. Vreysen Carlos Cacéres Todd E. Shelly Jorge Hendrichs 《Insect Science》2015,22(5):661-669
Methyl‐eugenol (ME) (1,2‐dimethoxy‐4‐(2‐propenyl)benzene), a natural phytochemical, did enhance male Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae) mating competitiveness 3 d after ingestion. Enhanced male mating competitiveness can significantly increase the effectiveness of the sterile insect technique (SIT). ME application to mass reared sterile flies by feeding is infeasible. ME application by aromatherapy however, would be a very practical way of ME application in fly emergence and release facilities. This approach was shown to enhance mating competitiveness of B. carambolae 3 d posttreatment (DPT). Despite this added benefit, every additional day of delaying release will reduce sterile fly quality and will add cost to SIT application. The present study was planned to assess the effects of ME‐aromatherapy on male B. carambolae mating competitiveness 1DPT and 2DPT. ME aromatherapy 1DPT or 2DPT did enhance mating competitiveness of B. carambolae males whereas ME feeding 1DPT and 2DPT did not. Male mating competitiveness was enhanced by the ME aromatherapy irrespective if they received 1DPT, 2DPT or 3DPT. ME aromatherapy, being a viable approach for its application, did enhance mating competitiveness of male B. carambolae 1 d posttreatment as ME feeding did 3 d after ingestion. 相似文献
380.