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Synthetic dyes are resistant to self-degradation in aqueous systems that pose severe health hazards to marine life. This work focuses on the comparative adsorption evaluation of synthesized biochar derived from green coffee wastes (GCB) and NaOH-modified GCB (NaOH-GCB) for the removal of anionic dyes (Eriochrome Black T and Congo Red) in aqueous solution. The characterization results of NaOH-GCB indicate higher thermal stability, improved surface functionality with -OH groups, smaller particle size (from 2–15 µm decreased to 0.5–1 µm), higher pore volume (increase from 0.0027 to 0.003 cm3/g), and higher surface area (increase from 2.91 to 3.22 m2/g) which enhanced dye adsorption. The maximum adsorption capacity was attained using NaOH-GCB with values of 119.37 mg/g and 91.54 mg/g recorded for EBT and CR, respectively. For both adsorbents, the optimal removal for EBT and CR dyes was obtained at solution pH 2 and 7 due to electrostatic and hydrogen bonding interactions. CR had slightly lower removal than EBT due to its hydrophobic nature. Pseudo-second order and Redlich-Peterson were the most effective models in providing insights about the adsorption kinetics and isotherm, with the system being heterogeneous and involving multi-layer behavior. Additionally, thermodynamics elucidated the adsorption to be spontaneous and exothermic. After five reusability cycles, the NaOH-GCB indicated excellent performance of over 90% removal for both dyes. The results show that NaOH-GCB is potentially an economical adsorbent for efficient and effective remediation of dye-contaminated wastewater streams.

A comprehensive and integrated exact analytical formalism is presented for erbium-doped fiber amplifiers and lasers (EDFALs) in one single configuration based on solutions of a system of rate and propagation equations represented by a homogenously broadened four band transition scheme while incorporating amplified spontaneous emission and excited state absorption effects. The formalism, under steady-state conditions, concurrently provides considerable insight into physical characteristics underlying phenomena pertinent to EDFALs and allows precise evaluation of behavior exhibited by EDFALs through a judicious selection of pump intensity and fiber length in standard eye-safe low-erbium concentration uniformly doped mono-mode silica glass fibers in co- and counter- propagating directions appropriate to signal, pump and ASE regimes.

Colorectal cancer (CC) is the third most common cancer in the world. Annona reticulata(AR) also known as bullock's heart, is a traditional herb. AR leaf extract was initially investigated for its anti-bacterial, anti-inflammatory, anti-malarial, anti-helminthic, anti-stress, and wound healing properties. Only a few in vitrocancer studies have been conducted on AR. Although few studies have linked AR leaf extract to many cancers, comprehensive studies addressing regulation, biological functions, and molecular mechanisms leading to CC pathogenesis are clearly lacking.

Aggregation of human α-synuclein (αSyn) is linked to Parkinson’s disease (PD) pathology. The central region of the αSyn sequence contains the non-amyloid β-component (NAC) crucial for aggregation. However, how NAC flanking regions modulate αSyn aggregation remains unclear. Using bioinformatics, mutation and NMR, we identify a 7-residue sequence, named P1 (residues 36–42), that controls αSyn aggregation. Deletion or substitution of this ‘master controller’ prevents aggregation at pH 7.5 in vitro. At lower pH, P1 synergises with a sequence containing the preNAC region (P2, residues 45–57) to prevent aggregation. Deleting P1 (ΔP1) or both P1 and P2 (ΔΔ) also prevents age-dependent αSyn aggregation and toxicity in C. elegansmodels and prevents αSyn-mediated vesicle fusion by altering the conformational properties of the protein when lipid bound. The results highlight the importance of a master-controller sequence motif that controls both αSyn aggregation and function—a region that could be targeted to prevent aggregation in disease.

In South Africa, there are limited nationally representative data on the prevalence and factors associated with psychological distress. This study used a 2012 nationally representative population-based household survey to investigate factors associated with psychological distress in South Africa.

Steadystate flow with replenishment to horizontal tube drains in a two layered soil has been simulated in a vertical HeleShaw model. Comparison of analytical solution of Toksoz and Kirkham on the simulated flow system shows good agreement.

To determine whether the activation of innate immune responses, which can be elicited by pathogenic and endogenous triggers, is associated with the presence of Epstein-Barr virus (EBV) infection in the multiple sclerosis (MS) brain.

Cervical cancer (CC) is the fourth most common gynecological malignancy globally. This suggests the need for improved markers for prognosis, better understanding of the molecular mechanism, and targets for therapy. The defective exocytosis pathway is proposed as bona fide drivers of carcinogenesis. This study aimed to identify the exocytosis pathway network and its contribution to CC.

Abstract??The possibility is substantiated for modeling gravitational flow of free-flowing bulk materials during discharge. Parameters are determined which provide dynamic similarity of the model to real conditions that are confirmed by experiment.

The infrared absorption spectra of vacuum-evaporated MoO3-In2O3 thin films are reported for a series of films of varying compositions within the spectral range 4000 to 400 cm-1 and interpreted in relation to the spectrum of the pure MoO3 films. The affects of changes in composition, film thickness, substrate deposition temperature and annealing on the absorption bands are observed. In some cases a shift in band frequency is also observed. The gradual increase in ordering and decrease in valency state with increase of annealing temperature is observed in the infrared curves. Some new peaks appear which reveal the presence of a lower valency state in MoO3. The shift in band frequency may be attributed to the incorporation of Mo(VI) ions in the indium interstitial positions.

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Limbic seizures were evoked in freely moving rats by intrahippocampal administration of the muscarinic agonist pilocarpine via the microdialysis probe (10 mM for 40 min at 2 microl/min). This study monitored changes in extracellular hippocampal gamma-aminobutyric acid (GABA), glutamate and dopamine levels after systemic (30 mg/kg/day) or local (intrahippocampal or intranigral, 5 mM or 600 microM for 180 min at 2 microl/min) vigabatrin administration, and evaluated the effectiveness of this antiepileptic drug against pilocarpine-induced seizure activity. Extracellular GABA and glutamate overflow in the ipsilateral cerebellum was studied simultaneously. Microdialysis was used as an in vivo sampling technique and as a drug-delivery tool. Electrophysiological evidence for the presence or absence of seizures was recorded with electrocorticography. The observed alterations in extracellular hippocampal amino acid levels support the hypothesis that muscarinic receptor stimulation by the intrahippocampal administration of 10 mM pilocarpine is responsible for the seizure onset, and that the amino acids maintain the sustained seizure activity. The focally evoked pilocarpine-induced seizures were completely prevented by intraperitoneal vigabatrin premedication for 7 days or by a single intraperitoneal injection. Effective protection was reflected in a lack of sustained elevations of hippocampal glutamate levels. Rats receiving vigabatrin intrahippocampally or intranigrally still developed seizures, although there appeared to be a partial protective effect. During the intrahippocampal perfusion with 5 mM vigabatrin, extracellular hippocampal GABA levels increased, whereas the extracellular glutamate and dopamine overflow decreased. The lack of a complete neuroprotection after local vigabatrin treatment is discussed.

Steady‐state flow with replenishment to horizontal tube drains in a two layered soil has been simulated in a vertical Hele‐Shaw model. Comparison of analytical solution of Toksoz and Kirkham on the simulated flow system shows good agreement.

D.c. electrical properties of SiOx-SnO (300 nm) thin films forming part of a metal-insulatormetal (MIM) structure are reported. The conduction process is related to the field-assisted thermal excitation of electrons from the trapping centres in the forbidden band gap to the conduction band (Poole-Frenkel effect). The energy gap between the trapping level and the bottom of the conduction band in 80% SiOx-20% SnO in thin films (300 nm) is found to be equal to 0.50 eV. The level of conduction in the composite films is observed to increase with an increase in the content of SnO.

The fundamental absorption edge of co-evaporated SiOx/SnO thin films of various compositions has been investigated. The results have been analysed by assuming optical absorption by non-direct electronic transitions. The optical energy gap is seen to decrease with increase in the molar content of SnO which increases the level of disorder of the complex system. The effect of substrate temperature during deposition on the optical absorption is also studied. The optical energy gap increases with the substrate temperature. This is attributed to the annealing of some of the dangling bonds and hence to an increase in the order of the system. The Urbach tail is related to the broadening of the absorption edge as a result of charged defects present in the films and related to the Franz-Keldysh effect.

The optical absorption spectra of evaporated V2O5 and co-evaporated V2O5/B2O3 thin films have been studied. For higher photon energies, the absorption is found to be due to a direct forbidden electronic transition process from the oxygen 2p band to the vanadium 3d band in a similar way to that observed in crystalline V2O5. The exponential behaviour of absorption edge for lower photon energies is attributed to the electronic transitions between the tailed-off d-d states corresponding to V4+ ions. For co-evaporated V2O5/B2O3 films the optical energy gap is observed to increase with the increase in V2O5 content of the composite films.

Clinical specimens from 317 patients suspected of cytomeglovirus infection were examined by immunofluorescence (IF) using monoclonal antibodies and by a biotinylated DNA probe kit after cell culture isolation. Of the 317 samples, 68 were positive by culture isolation. Of these 67 were IF positive when the cytopathic effect (CPE) was 1+ or less, whereas 56 gave positive results with DNA probes when the CPE was 2+. A further 83 specimens were examined directly by immunoperoxidase histopathology (IHP), IF and the DNA probe kit: 26 of these were positive by IHP examination, 25 by IF and only 6 by DNA probes. The sensitivity of the DNA probe kit was not satisfactory when the clinical tissue specimens were directly examined. However, the sensitivity improved considerably to 82% if the specimens were propagated first in cell culture. The IF method detected the virus before and after cell culture isolation equally well (96%–98.5%). Compared to the IF method, the DNA probe kit is costly and requires more labor and time.

Hereditary forms of chronic idiopathic intestinal pseudo-obstruction (CIIP) are well described but the aetiology of most cases of sporadic CIIP is unknown.

The electrical conduction through vacuum-evaporated thin films of V2O5 and V2O5/B2O3 in MIM structures has been investigated. The high-field behaviour of both types of film is in accordance with the Poole-Frenkel type of mechanism. The increase in B2O3 content in co-evaporated V2O5/B203 films results in a decrease in the conductivity of the composite films. This is attributed to the expansion of the resultant film structure due to the network-forming effect of B2O3. The covaporated thin films of V2O5/B2O3 with a molar content of B2O3 larger than 40% are observed to be unstable because of their hygroscopic nature.

The purpose of this study was to examine and compare the reliability and validity of two acne-specific measures, the Cardiff Acne Disability Index (CADI), the Acne Disability Index (ADI) and a general health status instrument, the United Kingdom Sickness Impact Profile (UKSIP). The test-retest reliability was carried out for the UKSIP, ADI and CADI with an interval of 10 days in 70 patients with acne. The correlation coefficient for the overall UKSIP score was high (r=0.99, p<0.001) for the CADI was 0.96 (p<0.001) and for the ADI was 0.98 (p<0.001). Individual category score correlations in the UKSIP and ADI were greater than 0.83. Tests of internal consistency of the instruments scored highly. A further 100 patients with acne and 50 controls completed all three instruments. The overall UKSIP mean score of patients was 5.6 (sd=4.7) and of controls was 0.45. The ADI mean patient score was 40.3%, controls 17.6%. The CADI mean patient score was 42.1%, controls 13.2%. The CADI was the only instrument that correlated with the clinical acne severity score (p<0.05); the UKSIP score correlated with the CADI score (p<0.05) but not with the ADI score. This study has established aspects of the reliability and validity of the UKSIP, the ADI and the CADI.

The effects of composition and substrate temperature during evaporation and annealing, on the electron spin resonance spectra of co-evaporated SiOx/SnO (300 nm) thin films have been investigated. The spin density is observed to decrease with increasing SnO content. This effect is attributed to the saturation of some of the paramagnetic defects such as dangling bonds and other structural defects like E'1 centres. The decrease in spin density in the composite thin films of SiOx/SnO of constant thickness and composition with annealing and with increase in the substrate temperature during evaporation, is related to the conversion of some of the paramagnetic E'1 centres to E?1 (probable non-paramagnetic precursor of E'1) centres as well as to the saturation of some of the dangling bonds.