1,022 research outputs found
PENGARUH KONSENTRASI MALTODEKSTRIN DAN SUHU PENGERINGAN TERHADAP KARAKTERISTIK PEWARNA ALAMI DAUN BAYAM MERAH (Alternathera amoena Vos) DENGAN METODE FOAM-MAT DRYING
Tujuan dari penelitian ini bertujuan untuk menentukan konsentrasi
maltodekstrin dan suhu pengeringan pada serbuk pewarna alami daun bayam merah
dengan metode foam-mat drying.
Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok
(RAK) dengan pola Faktorial 3x4 dengan ulangan sebanyak 3 kali. Adapun faktor
yang digunakan adalah konsentrasi maltodekstrin (a) sebanyak 3 taraf (a1
= 5%, a2
= 7,5%, a3
= 10%) dan suhu pengeringan (b) (b1
= 40°C, b2
= 50°C, b3
= 60°C).
Respon pada penelitian ini adalah kadar air (%), rendemen (%), kelarutan (%),
warna dengan kolorimetri L* a* b*, panjang gelombang maksimum, nilai Rf dan
stabilitas warna.
Hasil penelitian menunjukan bahwa perlakuan kosentrasi maltodekstrin
memberikat pengeruh nyata terhadap kelarutan serbuk pewarna dari daun bayam
merah. Perlakuan variasi suhu pengeringan memberikan pengeruh nyata terhadap
kadar air, intensitas kecerahan (L) dan intentitas warna kuning (b). Interaksi
konsentrasi maltodekstrin dan suhu pengeringan memberikan pengaruh nyata
terhadap intensitas warna merah (a). Berdasarkan uji skoring pada hasil penelitian
utama produk berpilih yaitu a3b2 (maltodekstrin 10% dan suhu pengeringan 50°C
dengan kadar air 4,37%, kecerahan (L) 42,04, warna merah (a) 17,58 warna kuning
(b) 3,21, kelarutan 89,96%, panjang gelombang 520 nm, nilai Rf 0,45, dan
berdasarkan uji kestabilan pada suhu 27°C penyimpanan 7 hari memiliki kestabilan
yang cukup baik.
Kata Kunci : Pewarna Alami, Daun Bayam Merah, dan Antosianin
PENGARUH SUMBER AIR BAKU DAN LOKASI SUMBER AIR BAKU YANG DIGUNAKAN TERHADAP KADAR MINERAL DAN KUALITAS YANG DIHASILKAN PADA PEMBUATAN AIR MINUM BEBAS MINERAL MELALUI PROSES DESTILASI
Air demineral yaitu air minum dalam kemasan yang diperoleh melalui proses pemurnian seperti : destilasi, deionisasi, reverse osmosis,dan proses setara. Tujuan dari penelitian ini adalah untuk menghasilkan air minum bebas mineral melalui proses destilasi yang berguna bagi kesehatan. Manfaat penelitian ini adalah dapat memberikan suatu variasi dalam produk pengolahan air, sehingga akan menghasilkan nilai komersial dari air. Selain itu dapat menghasilkan produk yang berguna bagi kesehatan. Rancangan yang digunakan yaitu rancangan percobaan dengan metode rancangan acak kelompok, rancangan analisis, dan rancangan respon yang meliputi : respon kimia seperti analisis kadar mineral (Fe2+, Ca2+, Mn2+, dan Mn2+), penentuan pH, dan respon organoleptik. Hasil dari penelitian pendahuluan diperoleh bahwa sumber air baku yang mengandung kadar besi, kalsium, magnesium, dan mangan paling tinggi yaitu masing – masing sumber air yang berasal dari air sumur dangkal panorama Kota Bandung (Fe2+ = 0,5194 ppm, Ca2+ = 64,1400 ppm, Mg2+ = 16,3655), dan air sumur artesis antapani Kota Bandung (Mn2+ = 1,6553 ppm). Sedangkan hasil untuk penelitian utama diperoleh bahwa semua sampel sumber air baku yang sudah didestilasi memiliki kadar Fe2+, Ca2+, Mn2+, dan Mn2+ = 0 , pH antara 5,0 – 7,0, dan respon organoleptik untuk parameter mutu rasa dan after taste di dapat hasil bahwa sumber air baku (A) dan interaksinya (A x B) berbeda nyata
High frequency diffraction of an electromagnetic plane wave by an imperfectly conducting rectangular cylinder
Copyright @ 2011 IEEEWe shall consider the the problem of determining the scattered far wave field produced when a plane E-polarized wave is incident on an imperfectly conducting rectangular cylinder. By using the the uniform asymptotic solution for the problem of the diffraction of a plane wave by a right-angled impedance wedge, in conjunction with Keller's method, the a high frequency far field solution to the problem is given
Electrostatically gated membrane permeability in inorganic protocells
Although several strategies are now available to produce functional microcompartments analogous to primitive cell-like structures, little progress has been made in generating protocell constructs with self-controlled membrane permeability. Here we describe the preparation of water-dispersible colloidosomes based on silica nanoparticles and delineated by a continuous semipermeable inorganic membrane capable of self-activated, electrostatically gated permeability. We use crosslinking and covalent grafting of a pH-responsive copolymer to generate an ultrathin elastic membrane that exhibits selective release and uptake of small molecules. This behaviour, which depends on the charge of the copolymer coronal layer, serves to trigger enzymatic dephosphorylation reactions specifically within the protocell aqueous interior. This system represents a step towards the design and construction of alternative types of artificial chemical cells and protocell models based on spontaneous processes of inorganic self-organization
Application of amorphous carbon based materials as antireflective coatings on crystalline silicon solar cells
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We report on the investigation of the potential application of different forms of amorphous carbon (a-C and a-C:H) as an antireflective coating for crystalline silicon solar cells. Polymeric-like carbon (PLC) and hydrogenated diamond-like carbon films were deposited by plasma enhanced chemical vapor deposition. Tetrahedral amorphous carbon (ta-C) was deposited by the filtered cathodic vacuum arc technique. Those three different amorphous carbon structures were individually applied as single antireflective coatings on conventional (polished and texturized) p-n junction crystalline silicon solar cells. Due to their optical properties, good results were also obtained for double-layer antireflective coatings based on PLC or ta-C films combined with different materials. The results are compared with a conventional tin dioxide (SnO(2)) single-layer antireflective coating and zinc sulfide/magnesium fluoride (ZnS/MgF(2)) double-layer antireflective coatings. An increase of 23.7% in the short-circuit current density, J(sc), was obtained using PLC as an antireflective coating and 31.7% was achieved using a double-layer of PLC with a layer of magnesium fluoride (MgF(2)). An additional increase of 10.8% was obtained in texturized silicon, representing a total increase (texturization + double-layer) of about 40% in the short-circuit current density. The potential use of these materials are critically addressed considering their refractive index, optical bandgap, absorption coefficient, hardness, chemical inertness, and mechanical stability. (C) 2011 American Institute of Physics. [doi:10.1063/1.3622515]1104Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Brazilian financial research agency MCTConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Anti-epileptic effect of Ganoderma lucidum polysaccharides by inhibition of intracellular calcium accumulation and stimulation of expression of CaMKII a in epileptic hippocampal neurons
Purpose: To investigate the mechanism of the anti-epileptic effect of Ganoderma lucidum polysaccharides (GLP), the changes of intracellular calcium and CaMK II a expression in a model of epileptic neurons were investigated.
Method: Primary hippocampal neurons were divided into: 1) Control group, neurons were cultured with Neurobasal medium, for 3 hours; 2) Model group I: neurons were incubated with Mg2+ free medium for 3 hours; 3) Model group II: neurons were incubated with Mg2+ free medium for 3 hours then cultured with the normal medium for a further 3 hours; 4) GLP group I: neurons were incubated with Mg2+ free medium containing GLP (0.375 mg/ml) for 3 hours; 5) GLP group II: neurons were incubated with Mg2+ free medium for 3 hours then cultured with a normal culture medium containing GLP for a further 3 hours. The CaMK II a protein expression was assessed by Western-blot. Ca2+ turnover in neurons was assessed using Fluo-3/AM which was added into the replacement medium and Ca2+ turnover was observed under a laser scanning confocal microscope.
Results: The CaMK II a expression in the model groups was less than in the control groups, however, in the GLP groups, it was higher than that observed in the model group. Ca2+ fluorescence intensity in GLP group I was significantly lower than that in model group I after 30 seconds, while in GLP group II, it was reduced significantly compared to model group II after 5 minutes.
Conclusion: GLP may inhibit calcium overload and promote CaMK II a expression to protect epileptic neuron
Prevalence and Determinants of Obesity among Primary School Children in Dar es Salaam, Tanzania.
Childhood obesity has increased dramatically and has become a public health concern worldwide. Childhood obesity is likely to persist through adulthood and may lead to early onset of NCDs. However, there is paucity of data on obesity among primary school children in Tanzania. This study assessed the prevalence and determinants of obesity among primary school children in Dar es Salaam. A cross sectional study was conducted among school age children in randomly selected schools in Dar es Salaam. Anthropometric and blood pressure measurements were taken using standard procedures. Body Mass Index (BMI) was calculated as weight in kilograms divided by the square of height in meters (kg/m2). Child obesity was defined as BMI at or above 95th percentile for age and sex. Socio-demographic characteristics of children were determined using a structured questionnaire. Logistic regression was used to determine association between independent variables with obesity among primary school children in Dar es Salaam. A total of 446 children were included in the analysis. The mean age of the participants was 11.1±2.0 years and 53.1% were girls. The mean BMI, SBP and DBP were 16.6±4.0 kg/m2, 103.9±10.3mmHg and 65.6±8.2mmHg respectively. The overall prevalence of child obesity was 5.2% and was higher among girls (6.3%) compared to boys (3.8%). Obese children had significantly higher mean values for age (p=0.042), systolic and diastolic blood pressures (all p<0.001). Most obese children were from households with fewer children (p=0.019) and residing in urban areas (p=0.002). Controlling for other variables, age above 10 years (AOR=3.3, 95% CI=1.5-7.2), female sex (AOR=2.6, 95% CI=1.4-4.9), urban residence (AOR=2.5, 95% CI=1.2-5.3) and having money to spend at school (AOR=2.6, 95% CI=1.4-4.8) were significantly associated with child obesity. The prevalence of childhood obesity in this population was found to be low. However, children from urban schools and girls were proportionately more obese compared to their counterparts. Primary preventive measures for childhood obesity should start early in childhood and address socioeconomic factors of parents contributing to childhood obesity
Status of the LUX Dark Matter Search
The Large Underground Xenon (LUX) dark matter search experiment is currently
being deployed at the Homestake Laboratory in South Dakota. We will highlight
the main elements of design which make the experiment a very strong competitor
in the field of direct detection, as well as an easily scalable concept. We
will also present its potential reach for supersymmetric dark matter detection,
within various timeframes ranging from 1 year to 5 years or more.Comment: 4 pages, in proceedings of the SUSY09 conferenc
Solution structure of a repeated unit of the ABA-1 nematode polyprotein allergen of ascaris reveals a novel fold and two discrete lipid-binding sites
Parasitic nematode worms cause serious health problems in humans and other animals. They can induce allergic-type immune responses, which can be harmful but may at the same time protect against the infections. Allergens are proteins that trigger allergic reactions and these parasites produce a type that is confined to nematodes, the nematode polyprotein allergens (NPAs). These are synthesized as large precursor proteins comprising repeating units of similar amino acid sequence that are subsequently cleaved into multiple copies of the allergen protein. NPAs bind small lipids such as fatty acids and retinol (Vitamin A) and probably transport these sensitive and insoluble compounds between the tissues of the worms. Nematodes cannot synthesize these lipids, so NPAs may also be crucial for extracting nutrients from their hosts. They may also be involved in altering immune responses by controlling the lipids by which the immune and inflammatory cells communicate. We describe the molecular structure of one unit of an NPA, the well-known ABA-1 allergen of Ascaris and find its structure to be of a type not previously found for lipid-binding proteins, and we describe the unusual sites where lipids bind within this structur
Long-term remission of myopic choroidal neovascular membrane after treatment with ranibizumab: a case report
<p>Abstract</p> <p>Introduction</p> <p>Myopia has become a big public health problem in certain parts of the world. Sight-threatening complications like choroidal neovascularisation membranes occur in up to 10% of pathological myopia, and natural history studies show a trend towards progressive visual loss. There are long-term financial and quality-of-life implications in this group of patients, and treatment strategies should aim for long-term preservation of vision.</p> <p>Case presentation</p> <p>A 56-year-old Caucasian woman presented with a best-corrected visual acuity of 6/6-1 in her right eye and 6/24 in her left. Fundal examination revealed pathological myopia in both eyes and an elevated lesion associated with pre-retinal haemorrhage in the left macula. Ocular coherence tomography and fundus fluorescein angiogram confirmed a subfoveal classic choroidal neovascularisation membrane. The patient decided to proceed with intravitreal ranibizumab (0.5 mg) therapy. One month after treatment, best-corrected visual acuity improved to 6/12 in her left eye, with complete resolution subretinal fluid on ocular coherence tomography. After three months, best-corrected visual acuity further improved to 6/9, which was maintained up to 16 months post-treatment.</p> <p>Conclusion</p> <p>We suggest intravitreal ranibizumab as an alternative treatment for long-term remission of myopic choroidal neovascular membrane. It also suggests that myopic choroidal neovascularisation membranes may require fewer treatments to achieve sustained remission. Furthermore, this could serve as a feasible long-term management option if used in conjunction with ocular coherence tomography.</p
- …