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1.
J Fluoresc ; 34(1): 411-424, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37278963

ABSTRACT

Cationic perylenediimide derivative, namely N,N'-di(2-(trimethylammoniumiodide)ethylene) perylenediimide (TAIPDI), has been synthesized and characterized in an aqueous medium by using dynamic light scattering (DLS), X-ray diffraction (XRD), fourier-transform infrared (FTIR), scanning electron microscope (SEM), and high-resolution transmission electron microscopy (HRTEM) techniques. The optical absorption and fluorescence spectra of TAIPDI revealed the formation of aggregated TAIPDI nanowires in water, but not in organic solvents. In order to control the aggregation behavior, the optical properties of TAIPDI have been examined in different aqueous media, namely cetyltrimethylammonium bromide (CTAB), and sodium dodecyl sulfate (SDS). Furthermore, the utilization of the examined TAIPDI for constructing supramolecular donor-acceptor dyad has been achieved by combining the electron accepting TAIPDI with the electron donating 4,4'-bis (2-sulfostyryl)-biphenyl disodium salt (BSSBP). The formed supramolecular dyad TAIPDI-BSSBP through the ionic and electrostatic π-π interactions have been well examined by various spectroscopic techniques, e.g., steady-state absorption and fluorescence, cyclic voltammetry, and time-correlated single-photon counting (TCSPC), and first principle computational chemistry methods. Experimental results suggested the occurring of intra-supramolecular electron transfer from BSSBP to TAIPDI with rate constant and efficiency of 4.76 × 109 s-1 and 0.95, respectively. The ease of construction, absorption in the UV-Visible region, and fast electron transfer process render the supramolecular TAIPDI-BSSBP complex as a donor-acceptor material for optoelectronic devices.

2.
Prostate ; 83(14): 1373-1386, 2023 10.
Article in English | MEDLINE | ID: mdl-37469120

ABSTRACT

BACKGROUND: Salvage cryotherapy (SCT) is widely used to treat prostate cancer (PCa) recurrence after radiotherapy (RT). We studied the intermediate oncological and functional outcomes of patients who underwent SCT following cryotherapy (CRYO-SCT) recurrence and compare it to recurrence after brachytherapy (BT-SCT). METHODS: An IRB-approved retrospective cohort study utilizing patient data from the Cryo On-Line Data Registry and the Duke PCa database between 1992 and 2016. Biochemical recurrence (BCR) using Phoenix criteria was the primary endpoint assessed at 2- and 5-years post-SCT. Secondary endpoints assessed functional outcomes including urinary continence, erectile function, and recto-urethral fistula. Association between treatment and biochemical progression-free survival was assessed using inverse probability weighted (IPTW) Cox proportional hazards regression. The differences in the secondary functional outcomes were assessed by Pearson's χ2 test or Fisher's exact test, corrected for IPTW. RESULTS: A total of 194 patients met inclusion criteria. The BCR rate for BT-SCT and CRYO-SCT was 23 (20.4%) and 17 (21%) at 2 years and 30 (26.5%) and 22 (27.2%) at 5 years according to Phoenix criteria. There was no statistical difference in 2 years (hazard ratio [HR] 0.9; 95% confidence interval [CI], 0.5-1.7, p = 0.7) or 5-year BCR (HR: 0.86; 95% CI, 0.5-1.5, p = 0.6) between the groups. The functional outcomes like urinary continence (p = 0.4), erectile function (p = 0.1), and recto-urethral fistula (p = 0.3) were not statistically different. CONCLUSION: CRYO-SCT appears to be well tolerated, with comparable oncological and functional outcomes to patients failing primary BT. The findings also demonstrated that SCT can render a significant number of patients biochemically free of disease after initial CRYO with minimal morbidity. SCT is a viable treatment option to salvage local PCa recurrence following either BT or cryoablation failure.


Subject(s)
Brachytherapy , Erectile Dysfunction , Fistula , Prostatic Neoplasms , Male , Humans , Brachytherapy/adverse effects , Erectile Dysfunction/etiology , Prostate-Specific Antigen , Retrospective Studies , Propensity Score , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Recurrence, Local/surgery , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Cryotherapy/adverse effects , Fistula/etiology , Fistula/therapy , Salvage Therapy , Treatment Outcome
3.
ACS Appl Bio Mater ; 5(12): 5645-5656, 2022 12 19.
Article in English | MEDLINE | ID: mdl-36446396

ABSTRACT

A hernia is a pathological condition caused by a defect or opening in the muscle wall, which leads to organs pushing through the opening or defect. Hernia recurrence, seroma, persistent pain, tissue adhesions, and wound infection are common complications following hernia repair surgery. Infection after hernia mesh implantation is the third major complication leading to hernia recurrence. In order to reduce the incidence of late infections, we developed a polypropylene mesh with antibacterial properties. In this study, knitted polypropylene meshes were exposed to radio-frequency plasma to activate their surfaces. The antibacterial monomer diallyldimethylammonium chloride (DADMAC) was then grafted onto the mesh surface using pentaerythritol tetraacrylate as the cross-linker since it is able to engage all four functional groups to form a high-density cross-linked network. The subsequent antibacterial performance showed a 2.9 log reduction toward Staphylococcus aureus and a 0.9 log reduction for Escherichia coli.


Subject(s)
Hernia, Ventral , Surgical Mesh , Humans , Surgical Mesh/adverse effects , Polypropylenes , Hernia, Ventral/drug therapy , Anti-Bacterial Agents/pharmacology
4.
Materials (Basel) ; 14(9)2021 Apr 23.
Article in English | MEDLINE | ID: mdl-33922496

ABSTRACT

In this paper, an integrated numerical model is proposed to investigate the effects of particulate size and volume fraction on the deformation, damage, and failure behaviors of particulate-reinforced metal matrix composites (PRMMCs). In the framework of a random microstructure-based finite element modelling, the plastic deformation and ductile cracking of the matrix are, respectively, modelled using Johnson-Cook constitutive relation and Johnson-Cook ductile fracture model. The matrix-particle interface decohesion is simulated by employing the surface-based-cohesive zone method, while the particulate fracture is manipulated by the elastic-brittle cracking model, in which the damage evolution criterion depends on the fracture energy cracking criterion. A 2D nonlinear finite element model was developed using ABAQUS/Explicit commercial program for modelling and analyzing damage mechanisms of silicon carbide reinforced aluminum matrix composites. The predicted results have shown a good agreement with the experimental data in the forms of true stress-strain curves and failure shape. Unlike the existing models, the influence of the volume fraction and size of SiC particles on the deformation, damage mechanism, failure consequences, and stress-strain curve of A359/SiC particulate composites is investigated accounting for the different possible modes of failure simultaneously.

5.
Phys Chem Chem Phys ; 22(40): 23169-23184, 2020 Oct 21.
Article in English | MEDLINE | ID: mdl-33025980

ABSTRACT

Herein, we report the design and synthesis of four new thiophene-bridged D-π-A configured organic dyes T1-4 comprising different donors, π-spacers and anchoring units, as potential sensitizers and co-sensitizers for DSSCs. The current work also highlights their structural, photophysical, thermal, electrochemical, theoretical, and photoelectrochemical studies, including evaluation of their structure-property relationships. The optical results revealed that the dyes T1-4 display λabs and λemi in the range of 402-461 nm and 556-575 nm, respectively, with a bandgap in the order of 2.31-2.58 eV. Furthermore, the results showed that the dyes possess all the pre-requisites to act as sensitizers/co-sensitizers. Among the tested dyes, the device based on sensitizer T2 achieved the highest PCE compared to the other three dyes, under the standard conditions. Furthermore, their co-sensitized devices were fabricated by co-adsorbing them with the well-known Ru-based MH-12 sensitizer and interestingly the co-sensitizer T3 carrying an alkoxy group and a barbituric acid anchor displayed the highest PCE of 8.79%, which is much higher than that of MH-12 alone (8.18%). Conclusively, the study furnishes a deeper understanding of the intricacies involved in the structural modification of sensitizers/co-sensitizers in achieving an enhanced performance of the devices.

6.
Plants (Basel) ; 9(9)2020 Aug 24.
Article in English | MEDLINE | ID: mdl-32847047

ABSTRACT

Frangula alnus and Peganum harmala populations growing in Saudi Arabia might be rich sources of natural compounds with important biological activities. A high performance liquid chromatography diode array revealed several polyphenols in the leaf extracts for the first time, including p-coumaric acid, rosmarinic acid, chlorogenic acid, ferulic acid, quercitrin, rutoside, quercetin and trifolin in F. alnus; and hydrocaffeic acid, protocatechuic acid, rosmarinic acid, caffeic acid and cynaroside in P. harmala. F. alnus and P. harmala showed strong antioxidant effects attributed to the polyphenolic composition of leaves and reduction of reactive oxygen species (ROS) accumulation. F. alnus and P. harmala leaf extracts showed cytotoxic effects against Jurkat, MCF-7, HeLa, and HT-29 cancer cells using MTT and flow cytometry assays. These activities were attributed to the polyphenolic composition of leaves including quercitrin, trifolin and cymaroside, as well as the activation of caspase family enzymes 2, 6, 8 and 9 in treated cancer cells compared to control. The current findings of this study include a novel comprehensive investigation on the polyphenol composition and anticancer effects of leaf extracts of F. alnus and P. harmala from natural populations in Saudi Arabia.

7.
Photochem Photobiol Sci ; 19(2): 281-288, 2020 Feb 19.
Article in English | MEDLINE | ID: mdl-31984988

ABSTRACT

The photophysical and electrochemical properties of new targeted 2-cyanoacetanilide-based dyes are illustrated. New cyanoacetanilides SA7-10 were synthesized and employed as co-sensitizers in DSSCs. The chemical structures of these 2-cyanoacetanilides differ according to the substituent at the benzene ring (-H, -Me, -OMe and -NEt2), with the anchoring moiety being the same, a -COOH group. Furthermore, a density functional theory (DFT) calculation has shown an effective intermolecular charge transfer character, the HOMOs of SA7-10 are mainly located on the corresponding donor part, and their LUMOs are located on carboxylic acid moieties as the acceptor. Interestingly, using photosensitizers SA7-10 as co-sensitizers with HD-2 dye causes an improvement in their photovoltaic performances. Among the dyes, SA10 co-sensitized with HD-2 displayed an overall efficiency of 8.25%, a JSC of 19.5 mA cm-2, a VOC of 0.65 V and an FF of 64.35 compared to 7.46%, 19 mA cm-2, 0.64 V and 60.54, respectively, of HD-2 only. Moreover, the electrochemical impedance spectroscopy (EIS) data of SA7-10 and HD-2 were found to be in accordance with the obtained photovoltaic parameters. Finally, the results indicated that 2-cyanoacetanilide-based dyes were utilized as promising co-sensitizers due to their easy preparation methods and their relatively small size.

8.
RSC Adv ; 10(47): 27940-27953, 2020 Jul 27.
Article in English | MEDLINE | ID: mdl-35685026

ABSTRACT

A new bipyridyl Ru(ii) sensitizer incorporating triphenylamine and the 3,4-ethylenedioxythiophene (EDOT) ancillary ligand IMA5 was synthesized for dye-sensitized solar cells (DSSCs). The performance of these DSSCs has been enhanced via di-anchoring metal-free organic sensitizers, denoted IMA1-4, with structural motif A-π-D-π-A and incorporating phenyl-dibenzothiophene-phenyl (Ph-DBT-Ph) as the main building block but with different anchoring groups (A). These new organic sensitizers were well-characterized and used as efficient co-sensitizers. Their photophysical, electrochemical and photovoltaic properties were studied. Furthermore, molecular modeling studies using DFT calculations were used to investigate their suitability as effective sensitizers/co-sensitizers. The molecular orbital isodensity showed distinguishable delocalization of the intramolecular charge in the DBT moiety. The photovoltaic characterization showed that IMA3 had the best DSSC performance (η = 2.41%). In addition, IMA1-4 was co-sensitized in conjunction with the newly synthesized IMA5 complex to enhance light harvesting across expanded spectral regions and thus improve efficiency. The solar cells co-sensitized with IMA2, IMA3 and IMA4 exhibited improved efficiency (η) of 6.25, 6.19 and 5.83%, respectively, which outperformed the device employing IMA5 alone (η = 5.54%) owing to the improvement in the loading of IMA2, IMA3 and IMA4 in the presence of IMA5 on the surface of the TiO2 nanoparticles, and charge recombination was suppressed.

9.
Phys Chem Chem Phys ; 21(20): 10603-10613, 2019 May 28.
Article in English | MEDLINE | ID: mdl-31074755

ABSTRACT

Herein, we report the design, synthesis and characterization of a new series of simple donor-π spacer-acceptor/anchor (D-π-A) type diphenylamine based metal-free organic dyes possessing three different anchoring groups, viz. 4-aminobenzoic acid (DTP), 2-(4-nitrophenyl)acetonitrile (DTN), and barbituric acid (DTB), connected with 2-(thiophene-2-yl)-acetonitrile, as effective sensitizers and co-sensitizers in Dye Sensitized Solar Cells (DSSCs). They were subjected to photophysical, electrochemical and theoretical studies. The dyes exhibited characteristic λabs and λemi in the range of 445-485 and 545-570 nm, respectively. Both optical and electrochemical band gaps were found to be in the range of 2.2 to 2.35 eV. The driving forces for injection (ΔGinj), recombination (ΔGrec) and regeneration (ΔGreg) processes were evaluated to understand their feasibility. Finally, the DSSC devices were fabricated employing the new dyes as sensitizers as well as co-sensitizers along with the Ru(ii) based N3 dye. Interestingly, DTP carrying 4-aminobenzoic acid as the anchoring group shows the best photoelectrochemical performance, viz. photovoltaic conversion efficiency (PCE) = 4.4%, open circuit potential (VOC) = 0.577 V, and short-circuit current density (JSC) = 9.06 mA cm-2 with a broad incident photon conversion efficiency (IPCE) spectrum. Co-sensitization of the dyes brought about enhanced VOC values, compared to the N3 dye alone. Finally, different interface resistance values obtained from the electrochemical impedance spectroscopy (EIS) circuit fitting were used to study the fundamental processes of energy conversion.

10.
Water Sci Technol ; 79(1): 175-187, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30816874

ABSTRACT

Supported liquid membranes (SLM) suffer from very slow mass transfer of the solute from the donor phase (DP) to the receptor phase (RP) through the liquid membrane (LM). In the present work, an attempt was made to accelerate the mass transfer in SLM by creating a modified configuration in which the DP and RP are made to flow either co- or counter-currently to each other. Variables, which could affect the removal of NaCl, were the volume ratio of DP to RP, type and quantity of sequestering agent (SA), presence of mobile carrier (MC), type of LM, and flow rate of DP and RP. The results showed that the higher the flow rate of DP and RP, the higher the mass transfer of NaCl. Quantity and type of SA and type of LM were prime important factors. Remarkably, the time required for transfer of NaCl from DP to RP was reduced from several hours in the case of stagnant SLM to several minutes in the present work. The mass transfer of NaCl was analysed based on kinetic laws of two consecutive irreversible first-order reactions. The values achieved establish the process is diffusion controlled, and the membrane entrance rate constants increase directly with initial concentration (Ci) and inversely with quantity of SA.


Subject(s)
Membranes, Artificial , Sodium Chloride/chemistry , Diffusion , Kinetics , Models, Chemical , Solutions
11.
RSC Adv ; 10(1): 610-619, 2019 Dec 20.
Article in English | MEDLINE | ID: mdl-35492570

ABSTRACT

A novel Ru(ii) complex, denoted as IA-7, incorporating a bulky donor antenna, was synthesized and characterized as a promising inexpensive alternative to conventional p-n junction solar cells to study the influence of a bulky donor antenna on the light harvesting efficiency (LHE), ground and excited state oxidation potentials and total conversion efficiency of sunlight to electricity (% η) for dye-sensitized solar cells (DSSCs), and the device performance was compared to devices with MH-12 and MH-13 dyes. The incorporation of the bulky donor enriched triphenylamine (TPA) antenna resulted in a considerable increase in J SC and η values for DSSCs, where IA-7 outperformed MH-12 and MH-13 in terms of the total conversion efficiency and achieved a power conversion efficiency (η) of 8.86% under full sunlight irradiation (100 mW cm-2), compared to 8.09% for MH-12 and 8.53% for MH-13, which can be ascribed to the high open circuit voltage (V OC) of IA-7. Molecular engineering utilizing DFT/TD-DFT was employed to calculate the electronic properties of IA-7, including the HOMO/LUMO isosurfaces, the lowest singlet-singlet electronic transitions (E 0-0), and the ground and excited state oxidation potentials, which were in ideal agreement with the empirical results. The electronic distribution of IA-7 indicated that the HOMO is delocalized not only on Ru and NCS, but also on the substituted TPA, and the LUMO is delocalized over 4,4'-bipyridyl dicarboxylic acid.

12.
Data Brief ; 21: 675-683, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30377652

ABSTRACT

X-ray crystallography and DFT calculations were used to characterize the molecular nature and excited state properties of isomeric photostable azo dyes for textile fibers undergoing extensive sunlight exposure. Structural data in CIF files arising from X-ray analysis are reported and the complete files are deposited with the Cambridge Crystallographic Data Centre as CCDC 1548989 (https://www.ccdc.cam.ac.uk/structures/Search?Ccdcid=1548989) and CCDC 1548990 (https://www.ccdc.cam.ac.uk/structures/Search?Ccdcid=1548990). Data from calculating the vertical electronic excitation of 20 excited states for each dye and from calculating excited state oxidation potential (ESOP) and Frontier HOMO/LUMO isosurfaces are also presented. This data is related to the article "Molecular and excited state properties of isomeric scarlet disperse dyes" (Lim et al., 2018) [1].

13.
Photochem Photobiol Sci ; 17(3): 363, 2018 03 14.
Article in English | MEDLINE | ID: mdl-29419842

ABSTRACT

Correction for 'New di-anchoring A-π-D-π-A configured organic chromophores for DSSC application: sensitization and co-sensitization studies' by Praveen Naik et al., Photochem. Photobiol. Sci., 2018, DOI: 10.1039/c7pp00351j.

14.
Photochem Photobiol Sci ; 17(3): 302-314, 2018 Mar 14.
Article in English | MEDLINE | ID: mdl-29336461

ABSTRACT

Herein, we report the design and synthesis of three new un-symmetrical metal-free carbazole based organic dyes, E1-3 with A-π-D-π-A architecture, as effective di-anchoring sensitizers in DSSCs. The new entities comprise carbazole as a donor scaffold connected to three different units, viz. cyano acetic acid, 2,4-thiazolidinedione and barbituric acid as acceptor/anchoring units via vinylene and phenylene as π-spacers at 3- and 6-positions of the carbazole ring, respectively. Photophysical, electrochemical and theoretical studies were carried out in order to assess their feasibility as active sensitizers. Furthermore, their photoelectrochemical performances and charge transport properties in fabricated DSSCs were evaluated. The results revealed that the device fabricated with the E1 sensitizer displayed the highest PCE of 2.38% among the three dyes. Its JSC, VOC, and IPCE values were found to be 6.36 mA cm-2, 0.599 V, and 57%, respectively. Its enhanced performance is attributed to the presence of a highly electron withdrawing cyano acetic acid unit on either side of the carbazole core through appropriate π-spacers. Interestingly, the DFT study indicated that the electron cloud of the LUMO level has been shifted significantly towards the 2-cyano phenyl acrylic acid connected at the 6th position of the carbazole ring, when compared to the cyano acrylic acid linked at position 3, confirming efficient charge separation in E1. The assigned lifetimes of E1-3 obtained from EIS studies were found to be in accordance with experimentally obtained photovoltaic parameters. Furthermore, E1-3, when co-sensitized with NCSU-10 sensitizer in DSSCs, displayed higher VOC values, but lower PCE values than that of NCSU-10.

15.
Article in English | MEDLINE | ID: mdl-29238391

ABSTRACT

BACKGROUND: The Global Burden of Disease 2010 study reported the relative size of major depressive disorder (MDD) burden to be greater in the Middle East and North Africa than anywhere else. However, little research has been carried out to examine the comparative effectiveness of antidepressants in this region. OBJECTIVE: To assess and compare functioning levels in Middle Eastern patients with MDD treated with either duloxetine or a selective serotonin reuptake inhibitor (SSRI), and to examine the impacts of depression-related pain on functioning by the type of treatment. METHOD: This post-hoc analysis, which focused on Middle Eastern patients, used data from a 6-month prospective observational study that included 1,549 MDD patients without sexual dysfunction. Levels of functional impairment and depression-related pain were assessed using the Sheehan Disability Scale (SDS) and the modified Somatic Symptom Inventory, respectively. A mixed model with repeated measures (MMRM) was employed. RESULTS: The mean age of the patients was 37.3 (SD=8.4) years, and 34.6% were female. Patient functioning was, on average, moderately impaired at baseline, but improved substantially during follow-up in both the duloxetine (n=152) and the SSRI (n=123) cohorts. The MMRM results showed a lower level of functional impairment at 24 weeks in the duloxetine cohort than in the SSRI cohort (p<0.001). Pain severity at baseline was positively associated with functional impairment during follow-up only in the SSRI cohort (p=0.003). CONCLUSION: Duloxetine-treated MDD patients achieved better functioning than SSRI-treated patients. This treatment difference was partly driven by depression-related pain.

16.
Mol Pain ; 13: 1744806917740233, 2017.
Article in English | MEDLINE | ID: mdl-29056066

ABSTRACT

Context: Monoclonal antibodies are being investigated for chronic pain to overcome the shortcomings of current treatment options. Objective: To provide a practical overview of monoclonal antibodies in clinical development for use in chronic pain conditions, with a focus on mechanisms of action and relevance to specific classes. Methods: Qualitative review using a systematic strategy to search for randomized controlled trials, systematic and nonsystematic (narrative) reviews, observational studies, nonclinical studies, and case reports for inclusion. Studies were identified via relevant search terms using an electronic search of MEDLINE via PubMed (1990 to June 2017) in addition to hand-searching reference lists of retrieved systematic and nonsystematic reviews. Results: Monoclonal antibodies targeting nerve growth factor, calcitonin gene-related peptide pathways, various ion channels, tumor necrosis factor-α, and epidermal growth factor receptor are in different stages of development. Mechanisms of action are dependent on specific signaling pathways, which commonly involve those related to peripheral neurogenic inflammation. In clinical studies, there has been a mixed response to different monoclonal antibodies in several chronic pain conditions, including migraine, neuropathic pain conditions (e.g., diabetic peripheral neuropathy), osteoarthritis, chronic back pain, ankylosing spondylitis, and cancer. Adverse events observed to date have generally been mild, although further studies are needed to ensure safety of monoclonal antibodies in early stages of development, especially where there is an overlap with non-pain-related pathways. High acquisition cost remains another treatment limitation. Conclusion: Monoclonal antibodies for chronic pain have the potential to overcome the limitations of current treatment options, but strategies to ensure their appropriate use need to be determined.


Subject(s)
Antibodies, Monoclonal/pharmacology , Central Nervous System Sensitization/drug effects , Chronic Pain/drug therapy , Neuralgia/drug therapy , Animals , Diabetic Neuropathies/drug therapy , Humans , Treatment Outcome
17.
Phys Chem Chem Phys ; 19(31): 20847-20860, 2017 Aug 09.
Article in English | MEDLINE | ID: mdl-28745343

ABSTRACT

In this study, we report the synthesis of a novel heteroleptic Ru(ii)-sensitizer, (Ru(2,2'-bipyridine-4,4'-dicarboxylic acid)-4,4'-bis(4-piperidin-1-yl)phenyl ethenyl)-(2,2'-bipyridine) (NCS)2, denoted as SD-1; moreover, its photophysical, electrochemical, and photovoltaic performances were compared with those of N719 and K77-7 (N,N'-diaryl Ru-sensitizer, namely Ru(2,2'-bipyridine-4,4'-dicarboxylic-acid)-4,4'-bis(2-(4-N,N'-diphenylaminophenyl)ethenyl)-2,2'-bipyridine (NCS)2). The photovoltaic performance of SD-1 outperformed those of N-719 and K77-7, particularly in the red region, and the overall efficiency of SD-1 was 8.5% as compared to 8.0% of K77-7 and 7.7% of N719 under the same experimental device conditions. The superior light harvesting efficiency of SD-1 can be attributed to the strong electron donor sp3-nitrogen, which is attached to two sp3-carbons (dialkyl), whereas in the case of K77-7, all carbon atoms attached to the sp3-nitrogen are sp2, which decrease the electron density on the latter and minimize the electron-donating power of the ancillary ligand in K77-7. To gain a quantitative understanding of the electron density on nitrogen in SD-1 and K77-7, first-principle calculations using molecular and thermodynamic descriptors, such as frontier molecular orbitals, ground-state oxidation potential (GSOP), excited-state oxidation potential (ESOP), optical gap (E0-0), and charge distributions, were conducted in solution. In addition, for understanding the anchored structures of dyes on Ti24O48, density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were utilized. Results of computational studies are in excellent agreement with the experimental results, which can be used as a screening tool for the design of more efficient molecular motifs for DSSCs.

18.
Water Sci Technol ; 72(5): 785-93, 2015.
Article in English | MEDLINE | ID: mdl-26287838

ABSTRACT

An innovative polymeric membrane has been invented, which presents a breakthrough in the field of desalination membranes. It can desalinate simulated seawater of exceptionally high concentration to produce a high flux of potable water with over 99.7% salt rejection (%SR) in a once-through purge-air pervaporation (PV) process. A set-up was constructed for conducting the desalination experiments and the effect of initial salt solution concentration (Ci) and pervaporation temperature (Tpv) on the water flux (J), %SR, separation factor, and pervaporation separation index were determined. The membrane was prepared by the phase-inversion technique, of a specially formulated casting solution consisting of five ingredients, after which the membrane was subjected to a post-treatment by which certain properties were conferred. The results confirmed that the salinity of the pervaporate was independent of Ci (all %SR above 99.7). The best result was at Tpv=70 °C, where J varied from 5.97 to 3.45 l/m2 h for Ci=40-140 g NaCl/l, respectively. The membrane morphology was confirmed to be asymmetric. The contact angle was immeasurable, indicating the membrane to be super-hydrophilic. Activation energies computed using Arrhenius law were, under all conditions investigated, less than 20 kJ/mol K.


Subject(s)
Membranes, Artificial , Sodium Chloride/isolation & purification , Water Purification/instrumentation , Polymers , Salinity , Seawater , Solutions , Temperature , Water
19.
Urology ; 85(6): 1241-6, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25863835

ABSTRACT

OBJECTIVE: To investigate whether there is benefit with a longer acting oral fluoroquinolone, we compared the rate of infection after transrectal ultrasound-guided prostate biopsy between 2 prophylactic antibiotic regimens: ciprofloxacin vs levofloxacin, each combined with an aminoglycoside (AG). METHODS: A retrospective review was performed of all transrectal ultrasound-guided prostate biopsies from September 2011 to January 2013. Initially our regimen entailed 1 dose of 500-mg ciprofloxacin and an AG. In June 2012, we switched to 1 dose of 750-mg levofloxacin and an AG. Infections were categorized as severe if requiring hospital admission, overnight observation, or emergency room treatment for fever or chills. Those treated as an outpatient were defined as mild. RESULTS: Of 1189 total biopsies, the total infection rate was 3.18% (17 of 535) in the ciprofloxacin group and 2.14% (14 of 654) in the levofloxacin group (P = .26). The rate of mild infection was 0.75% (4 of 535) in the ciprofloxacin group and 1.22% (8 of 654) in the levofloxacin group (P = .56). The rate of severe infection was significantly higher in the ciprofloxacin group at 2.43% (13 of 535) compared with that of 0.92% (6 of 654) in the levofloxacin group (P = .04). On multivariate analysis, use of ciprofloxacin rather than levofloxacin was associated with an increased risk of severe infection (odds ratio, 4.59; P = .04). CONCLUSION: Empiric prophylaxis for prostate biopsies with a single-dose fluoroquinolone augmented with an AG is optimal to reduce infectious complications. We found 750-mg levofloxacin resulted in significantly fewer severe infections compared with 500-mg ciprofloxacin potentially because of its longer half-life.


Subject(s)
Aminoglycosides/administration & dosage , Anti-Bacterial Agents/administration & dosage , Antibiotic Prophylaxis , Bacterial Infections/prevention & control , Ciprofloxacin/administration & dosage , Fluoroquinolones/administration & dosage , Levofloxacin/administration & dosage , Postoperative Complications/prevention & control , Prostate/pathology , Drug Therapy, Combination , Humans , Image-Guided Biopsy/methods , Male , Middle Aged , Prostate/diagnostic imaging , Retrospective Studies , Severity of Illness Index , Ultrasonography, Interventional
20.
Urology ; 85(5): 1137-1142, 2015 May.
Article in English | MEDLINE | ID: mdl-25799176

ABSTRACT

OBJECTIVE: To define the effects of androgen deprivation therapy (ADT) used prior to salvage cryoablation (SC) for the treatment of recurrent localized prostate cancer after radiation. METHODS: Patients from the Cryo On-Line Database registry undergoing SC after radiation failure were divided according to whether they had previously received or not received ADT. Baseline characteristics including demographics and presalvage cancer risk were compared. Biochemical progression-free survival (bPFS) as defined by the Phoenix criteria was compared between the 2 groups as a whole and also in D'Amico risk-stratified subgroups. In addition, postsurgical complications such as urinary fistula, retention, incontinence, and erectile dysfunction were compared. RESULTS: Two groups consisting of 254 and 486 patients with and without pre-SC ADT were analyzed. The patients who received ADT were younger (P = .003) and had higher presalvage D'Amico risks (P <.001). The 5-year bPFS was 63.8% and 39.3% for the hormone-naïve and the pre-SC ADT patients, respectively (P <.001). On subgroup analysis, the difference in 5-year bPFS was significant only for patients with a high D'Amico cancer risk (54.3% vs 30.5%; P = .013). On multivariate analysis, presalvage prostate-specific antigen (hazard ratio [HR], 1.7), Gleason score ≥ 8 (HR, 2.5), and use of pre-SC ADT (HR, 1.7) correlated with biochemical recurrence. Additionally, patients receiving pre-SC ADT experienced less urinary retention (P = .001) and incontinence (P = .008) but were more likely to be impotent (P = .010). CONCLUSION: Patients receiving ADT before SC, especially those with high-risk prostate cancer, had worse 5-year bPFS. Added caution is needed when selecting patients having previously received ADT for salvage cryotherapy.


Subject(s)
Androgen Antagonists/therapeutic use , Cryosurgery , Prostatectomy/methods , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/surgery , Aged , Aged, 80 and over , Disease-Free Survival , Humans , Male , Middle Aged , Retrospective Studies , Salvage Therapy , Treatment Failure
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