Pengolahan Limbah Cair Industri Pewarnaan Jeans Menggunakan Membran Silika Nanofiltrasi Aliran Cross Flow Untuk Menurunkan Warna Dan Kekeruhan

Limbah cair industri tekstil disamping mengandung bahan pencemar organik yang tinggi, juga mengandung bahan pewarna organik rantai panjang yang relatif sukar diolah dengan proses biologis. Sedangkan proses pengolahan secara kimia seringkali kurang efektif dikarenakan biaya untuk pembelian bahan kimianya cukup tinggi dan pada umumnya pengolahan air limbah secara kimia akan menghasilkan sludge. Sehingga dipilih teknologi membran sebagai media filtrasi baik yang digunakan pada skala laboratorium maupun industri, proses berlangsung cepat, cara pengoperasian sederhana, mudah dalam penggandaan skala, tidak memerlukan ruang yang besar, dan dapat mendapatkan permeat dengan kualitas sangat baik. Pasir silika merupakan bahan yang dapat digunakan sebagai sumber silika untuk pembuatan membran. Metode yang digunakan untuk sintesis silika yaitu metode alkalifussion dikarenakan metode ini menghasilkan silika dengan kemurnian 99%.Membran silika merupakan membran yang terbuat dari silika dengan perekat poly vinyl alcohol (PVA), pengemulsi poly ethylen glykol (PEG), dan semen putih. Penelitian ini bertujuan untuk mengetahui pengaruh massa silika dan konsentrasi limbah terhadap koefisien rejeksi, fluks, struktur dan morfologi membran. Uji struktur dan morfologi membran dilakukan dengan FTIR serta SEM. Parameter yang digunakan pada penelitian ini adalah warna dan kekeruhan. Nilai koefisien rejeksi tertinggi sebesar 96,86% untuk warna dan 99,31% untuk kekeruhan yang diperoleh dari massa campuran silika 5 gram (28,65 %wt), volume limbah 100% dengan kandungan warna 1,123 Co dan kekeruhan 180,5 NTU. Nilai fluks tertinggi sebesar 3,432 liter.m-2.jam-1 yang diperoleh dari massa campuran silika 8 gram (39,12 %wt) dengan penggunaan volume limbah 25% yang mengandung warna 0,525 Co dan kekeruhan 40,9 NTU. Membran silika yang optimum untuk menurunkan warna dan kekeruhan diperoleh dari massa campuran silika 5 gram (28,65 %wt) dengan % volume limbah 100%

‘Give me a hug': the effects of touch and autonomy on people's responses to embodied social agents

Embodied social agents are programmed to display human-like social behaviour to increase intuitiveness of interacting with these agents. It is not yet clear to what extent people respond to agents’ social behaviours. One example is touch. Despite robots’ embodiment and increasing autonomy, the effect of communicative touch has been a mostly overlooked aspect of human-robot interaction. This video-based, 2x2 betweensubject survey experiment (N=119) found that the combination of touch and proactivity influenced whether people saw the robot as machine-like and dependable. Participants’ attitude towards robots in general also influenced perceived closeness between humans and robots. Results show that communicative touch is considered a more appropriate behaviour for proactive agents rather than reactive agents. Also, people that are generally more positive towards robots find robots that interact by touch less machine-like. These effects illustrate that careful consideration is necessary when incorporating social behaviours in agents’ physical interaction design

Partial restoration of the actin cytoskeleton in transformed Syrian hamster fibroblasts selected for low levels of ‘typical’ multidrug resistance

AbstractTwo independent colchicine (CLC)-resistant sublines of Rous sarcoma virus-transformed Syrian hamster flbroblasts were isolated. Each subline represented variants with 11- and 12.4-fold resistance, respectively, their 23- and 23.7-fold resistant descendants, as well as variants cultured in CLC-free medium for 10 months without loss of resistance. All variants demonstrated ‘typical’ multidrug resistance. The parental cells contained actin in dispersed form, as determined by rhodamine-phalloidin staining. In contrast, already in 11- and 12.4-fold resistant sublines up to 30% of cells demonstrated restored stress fibers. Cultivation in CLC-free medium leads to the accumulation of cells with a partially restored actin cytoskeleton. Putative mechanisms of up-regulation of stress fiber assembly in cells with P-glycoprotein-mediated multidrug resistance are discussed

List, group or menu: Organizing Suggestions in Autocompletion Interfaces

We describe two user studies that investigate organization strategies of autocompletion in a known-item search task: searching for terms taken from a thesaurus. In Study 1, we explored ways of grouping term suggestions from two different thesauri (TGN and WordNet) and found that different thesauri may require different organization strategies. Users found Group organization more appropriate to organize location names from TGN, while Alphabetical works better for WordNet. In Study 2, we compared three different organization strategies (Alphabetical, Group and Composite) for location name search tasks. The results indicate that for TGN autocompletion interfaces help improve the quality of keywords, Group and Composite organization help users search faster, and is perceived easier to understand and to use than Alphabetical

Representation of Africa online: sourcing practice and frames of reference

The dominant perspective on the representation of Africa in the western media claims that western media coverage is bias and crisis orientated and the liberal perspective claims that the coverage of Africa is not as negative as is often assumed. However, there is a paucity of literature on the representation of Africa online. This research enquiry is relevant because literature claims that the Internet has the potential to resolve the journalistic predicament of representing other culture through political participation and deliberation. But this requires a re-orientation of the sourcing practice of news organization to embrace sensitivity to and knowledge of African cultures. Moreover, the journalistic predicament can be resolved or not depending on the news gathering approach adopted by the news organization. Literature has identified two approaches, that is, ‘gatekeeping’ used mainly by dominant traditional media and ‘gatewatching’ used by alternative media in their quest to counter mainstream ideology. This study examines the impacts of the ‘gatewatching’ approach adopted by Africa Have Your Say (AHYS) website on its representation and frames of reference of Africa. It uses on-site observation, in-depth interviews and textual analysis to gather data. The study found that although the sourcing practice at the AHYS is elaborate and complex, the ‘gatewatching’ approach makes its susceptible to second level agenda setting. Hence, its frame repeats the attributes and tone used by the mainstream traditional media. However, a minority of users did not use repeat this frame in their comments

Properties of a cryptic lysyl oxidase from haloarchaeon Haloterrigena turkmenica

Background Lysyl oxidases (LOX) have been extensively studied in mammals, whereas properties and functions of recently found homologues in prokaryotic genomes remain enigmatic. Methods LOX open reading frame was cloned from Haloterrigena turkmenica in an E. coli expression vector. Recombinant Haloterrigena turkmenica lysyl oxidase (HTU-LOX) proteins were purified using metal affinity chromatography under denaturing conditions followed by refolding. Amine oxidase activity has been measured fluorometrically as hydrogen peroxide release coupled with the oxidation of 10-acetyl-3,7-dihydroxyphenoxazine in the presence of horseradish peroxidase. Rabbit polyclonal antibodies were obtained and used in western blotting. Results Cultured H. turkmenica has no detectable amine oxidase activity. HTU-LOX may be expressed in E. coli with a high protein yield. The full-length protein gives no catalytic activity. For this reason, we hypothesized that the hydrophobic N-terminal region may interfere with proper folding and its removal may be beneficial. Indeed, truncated His-tagged HTU-LOX lacking the N-terminal hydrophobic signal peptide purified under denaturing conditions can be successfully refolded into an active enzyme, and a larger N-terminal truncation further increases the amine oxidase activity. Refolding is optimal in the presence of Cu2+ at pH 6.2 and is not sensitive to salt. HTU-LOX is sensitive to LOX inhibitor 3-aminopropionitrile. HTU-LOX deaminates usual substrates of mammalian LOX such as lysine-containing polypeptides and polymers. The major difference between HTU-LOX and mammalian LOX is a relaxed substrate specificity of the former. HTU-LOX readily oxidizes various primary amines including such compounds as taurine and glycine, benzylamine being a poor substrate. Of note, HTU-LOX is also active towards several aminoglycoside antibiotics and polymyxin. Western blotting indicates that epitopes for the anti-HTU-LOX polyclonal antibodies coincide with a high molecular weight protein in H. turkmenica cells. Conclusion H. turkmenica contains a lysyl oxidase gene that was heterologously expressed yielding an active recombinant enzyme with important biochemical features conserved between all known LOXes, for example, the sensitivity to 3-aminopropionitrile. However, the native function in the host appears to be cryptic. Significance This is the first report on some properties of a lysyl oxidase from Archaea and an interesting example of evolution of enzymatic properties after hypothetical horizontal transfers between distant taxa