Performance comparison of differential space-time signalling schemes for OFDM systems

Differential transmit diversity is an attractive alternative to its coherent counterpart, especially for multiple antenna systems where channel estimation is more difficult to attain compared to that of single antenna systems. In this paper we compare two different types of differential transmit diversity techniques for OFDM based transmissions. The first technique uses differential space-time block codes (DSTBC) from orthogonal designs and the second uses the differential cyclic delay diversity (DCDD). The results compare the bit error performance for several transmit antenna configurations. The results show that DCDD offers a very close performance to that of DSTBC, with the advantage of a simplified receiver structure

XmnI polymorphism: Relation to β-thalassemia phenotype and genotype in Egyptian Children

Background: β-Globin mutations with Xmn1 site might be associated with elevatedHbF expression which may in turn ameliorate the severity of β-thalassemia phenotype.Aim of the study: To investigate the frequency of 158 (C > T) XmnI polymorphism among Egyptian Children and young adults with β-thalassemia, to examine the relationship between XmnI polymorphism and β-thalassemia genotypes and phenotypes and to assess the possible relation of XmnI polymorphism and response to hydroxyurea (Hu) therapy.Patients and methods: Seventy-two β-thalassemia patients (37 females; M/F ratio 0.95) with a mean age of 7.53 ± 6.99 were included. Laboratory investigations included Complete blood count (CBC), Hb electrophoresis by high performance liquid chromatography (HPLC), β-thalassemia mutation identification by the reverse dot blot hybridization technique (RDB) and detection of XmnlGg polymorphism by RFLP.Results: The frequency of positive heterozygote XmnI gene polymorphism was 8.3%. Eightythree percent of XmnIGγ+/- patients were never transfused (p= 0.001) and had higher total hemoglobin compared to XmnIGγ-/- (p= 0.01); while mean HbF was higher among XmnIGγ+/- patients compared to the other group but the difference was marginally insignificant (p=0.06).β-Thalassemia mutation IVS II-1 showed relatively higher XmnI polymorphism frequency (50%) and followed by its frequency among 10 undefined β-thalassemia mutations which was 20%. The frequency of positive heterozygote XmnI gene polymorphism was 11.6% among the TI group vs. 3.5% among the TM group (p= 0.4). Among 20 cases who received HU; 5/14 responders vs. 1/ 6 none responder had positive heterozygote XmnI gene polymorphism (p= 1.0).Conclusions and recommendations: In conclusion, molecular determination of genetic markers in childhood will help to identify phenotypes of our patients and to avoid over or under treatment strategies. Further prospective studies concerning the genetic markers that could predict the response to hemoglobin F inducers like hydroxyurea are highly recommended

Efecto sobre la oxidación de triglicéridos purificados del aceite de girasol, del extracto de acetona del fruto de Maclura pomifera, de la pomiferina y de la osajina

omiferin and osajin have been isolated from the acetonic extract of M. pomifera fruits. Effects of total acetonic extract, pomiferin and osajin on the autooxidation of purified sunflower triacylglycerol were studied. Pomiferin showed a high antioxidant activity whereas total acetonic extract showed moderate and osajin revealed a low activity.Se han aislado la pomiferina y la osajina del extracto de hexano del fruto de M. pomifera. Se han estudiado los efectos sobre la oxidación de triglicéridos purificados del aceite de girasol, del extracto de acetona, de la pomiferina y de la osajina. La pomiferina mostró una actividad antioxidante elevada en cambio, el extracto de acetona mostró una actividad moderada y la osajina baja

Pengaruh Kualitas Pelayanan, Promosi, Dan Harga Terhadap Keputusan Pmebelian Carrefour (Studi Kasus Pada Konsumen Carrefour Srondol)

Purchase decision is an act of consumers to want to buy the product or not. To be able to create a high purchasing decisions, Carrefour needs to consider factors - factors that influence purchase decisions. Quality of service, promotion, and price are the things to consider when consumers make a purchase decision.This research aimed to determine the effect of service quality, promotion, and price on purchase decisions at Carrefour simultaneously or partially. The hypothesis is there are significant quality of service, promotion, and pricing on purchasing decisions simultaneously or partially. This type of research is explanatory research with a population of 100 people Srondol Carrefour consumers. Data were collected through questionnaires with Likert scale measurement. Data analysis method used is correlation, simple and multiple linear regression using SPSS 21.This research concluded the quality of services, promotion and pricing influence on purchase decisions partially or simultan.Variabel service quality has a greater influence than promotions and price.Based on the results of this study concluded that consumer perception of quality of service, promotion, and price is fair. So companies are advised to keep increasing consumer purchasing decisions in terms of quality of service, promotion, and better pricing more in line with expectations and needs of the company, so that consumers will feel satisfied and purchasing decisions will increase

Penggunaan Modul Berbasis Kontekstual Terhadap Hasil Belajar Fisika Peserta Didik Pada Pokok Bahasan Hukum Newton Kelas VIII Mts. Madani Alauddin Paopao

Tujuan penelitian ini adalah menegetahui apakah modul fisika berbasis kontekstual dapat digunakan sebagai alternatif dalam proses pembelajaran pada kelas VIII MTs. Madani Alauddin Paopao Kab. Gowa. Populasi dalam penelitian ini adalah seluruh peserta didik kelas VIII MTs. Madani Alauddin Paopoa Kab. Gowa yang berjumlah 95 peserta didik. Dengan menggunakan teknik Random Class diperoleh sampel satu kelas dengan jumlah peserta didik sebanyak 31 orang. Instrumen penelitian yang digunakan yaitu kuesioner dan tes hasil belajar. Teknik analisis data yang digunakan yaitu analisis data statistik deskriptif dan inferensial. Berdasarkan analisis deskriptif untuk respons peserta didik terhadap modul fisika berbasisis kontekstual menunjukkan bahwa 97% dari jumlah keseluruhan peserta didik memberi respons positif dan sangat positif dengan rerata penilaian berada pada kategori 4,0 (senang). Tes hasil belajar peserta didik mencapai nilai rata-rata 83,55, berada pada kategori tinggi melebihi standar KKM yakni 75. Berdasarkan Hasil uji normalitas data diperoleh nilai signifikan 0,395, sehingga nilai Sig > α (0,05) maka data hasil belajar berasal dari populasi berdistribusi normal. Berdasarkan hasil uji hipotesis diperoleh thitung = 4,972 dan nilai ttabel = 1,697. Karena nilai thitung > ttabel maka H0 ditolak sehingga Ha diterima. Dengan demikian, hasil belajar sesudah diajarkan dengan menggunakan modul fisika berbasis kontekstual telah mencapai standar KKM

Purification and characterization of cyclodextrin glucanotransferase from alkalophilic Bacillus sp. G1

A cyclodextrin glucanotransferase (CGTase) was successively purified by ammonium sulphate precipitation, and affinity chromatography on a-CD (epoxy)-Sepharose 6B column. The specific activity of the CGTase was increased approximately 2200-fold, from 8.43 U/mg protein to 18,866 U/mg protein. SDS-PAGE showed that the purified CGTase was homogeneous and the molecular weight of the purified CGTase was about 75 kDa. The molecular weight of the enzyme that was estimated by gel filtration under native condition was 79 kDa. This has indicated that Bacillus sp. G1 CGTase is a monomeric protein. The isoelectric point (pI) of the enzyme was about 8.8. Characterization of the enzyme exhibited optimum pH and temperature of 6.0 and 60 8C, respectively. The enzyme was stable from pH 7.0 to 9.0 and retained its high activity up to 60 8C. However, in the presence of 20 mM Ca2+, the purified CGTase is able to prolong its thermal stability up to 70 8C. CGTase was strongly inhibited by ZnSO4, CuSO4, CoCl2, FeSO4, FeCl3 and EDTA. Km and Vmax for the purified enzyme were 0.15 mg/ml and 60.39 mg bcyclodextrin/( ml min), respectively, with soluble starch as substrate. In cyclodextrin production, tapioca starch was found to be the best substrate used to produce CDs. The enzyme produced g- and b-CD in the ratio of 0.11:0.89 after 24 h incubation at 60 8C, without the presence of any selective agents