Calculations of giant magnetoresistance in Fe/Cr trilayers using layer potentials determined from {\it ab-initio} methods

The ab initio full-potential linearized augmented plane-wave method explicitly designed for the slab geometry was employed to elucidate the physical origin of the layer potentials for the trilayers nFe/3Cr/nFe(001), where n is the number of Fe monolayers. The thickness of the transition-metal ferromagnet has been ranged from $n=1$ up to n=8 while the spacer thickness was fixed to 3 monolayers. The calculated potentials were inserted in the Fuchs-Sondheimer formalism in order to calculate the giant magnetoresistance (GMR) ratio. The predicted GMR ratio was compared with the experiment and the oscillatory behavior of the GMR as a function of the ferromagnetic layer thickness was discussed in the context of the layer potentials. The reported results confirm that the interface monolayers play a dominant role in the intrinsic GMR.Comment: 17 pages, 7 figures, 3 tables. accepted in J. Phys.: Cond. Matte

Penerapan Pendekatan Keterampilan Proses Untuk Meningkatkan Hasil Belajar Siswa Pada Mata Pelajaran IPA Di Kelas V SDN 04 Lakea

Tujuan penelitian ini adalah untuk meningkatkan hasil belajar belajar pada mata pelajaran IPA di kelas V SDN 04 Lakea Kabupaten Buol melalui penggunaan pendekatan keterampilan proses. Jenis penelitian ini adalah tindakan kelas yang bersiklus melalui empat tahap yaitu, perencanaan, pelaksanaan, observasi, dan refleksi. Subjek penelitian adalah siswa kelas V yang berjumlah 23 yang terdiri dari 14 orang perempuan dan 9 orang laki-laki. Jenis data dalam penelitian ini adalah aktivitas guru dan siswa dan hasil belajar siswa dalam memahami organ-organ tubuh manusia. Hasil penelitian menunjukkan ada peningkatan yang berarti baik pada aktivitas guru dan siswa pada saat proses belajar maupun hasil belajar. Peningkatan itu dapat dilihat pada setiap siklus yaitu pada tes awal daya serap klasikal 58%, lalu mengalami peningkatan pada siklus I menjadi 74,34% dan pada siklus II meningkat lagi menjadi 82,39%, sehingga tingkat keberhasilan daya serap klasikal berada pada kategori baik. Ketuntasan belajar klasikal dari tes awal 21,73% lalu pada siklus I 69,56% lalu meningkat lagi menjadi pada siklus II 95,65%, hal ini menunjukkan bahwa taraf keberhasilan pada siklus II berada pada kategori sangat baik. Berdasarkan data tersebut maka disimpulkan dengan menggunakan pendekatan keterampilan proses dapat meningkatkan hasil belajar siswa pada mata pelajaran IPA di kelas V SDN 04 Lakea Kabupaten Buol

Analisis Kebangkrutan pada PT. Sumalindo Jaya Lestari Tbk

Tujuan penelitian ini untuk mengetahui potensi kebangkrutan dengan menggunakan Altman Z-Score pada “PT.Sumalindo Jaya Lestari Tbk ( PT SLJ Global Tbk)”. Dengan hipotesis PT.Sumalindo Jaya Lestari Tbk ( PT SLJ Global Tbk) berpotensi mengalami kebangkrutan pada tahun 2011, 2012, 2013, dan 2014. Alat analisis yang digunakan untuk mengetahui potensi kebangkrutan dalam penelitian ini adalah model Altman Z-Score.Penelitian ini menggunakan metode Altman Z-Scor, Hal ini dibuktikan dari menurunnya penjualan serta rugi Perusahaan setiap tahunnya. Sehingga nilai Zi selalu dibawah 1,23 dan setiap tahun mengalami penurunan dan Perusahaan sangat besar berpotensi bangkrut.Dari hasil analisis dan pemahasan, maka dapat diambil kesimpulan bahwa dilihat dari tahun 2011 hingga 2014 PT.Sumalindo Jaya Lestari Tbk ( PT SLJ Global Tbk) kondisi keuangannya tidak sehat dan berpotensi keuangannya yang sangat besar beresiko tinggi sehingga kemungkinan bangkrutnya sangat besar, hal ini dibuktikan dari hasil nilai Zi pada tahun 2011 sebesar -0.5479, tahun 2012 sebesar -0.2787, tahun 2013 sebesar -0.2493, tahun 2014 sebesar 0.0996 yang berarti bahwa nilai Zi lebih kecil dari 1,23. Dimana apabila Zi kurang dari 1,23 maka Perusahaan tersebut dikategorikan sebagai Perusahaan yang kondisi keuangannya yang sangat besar beresiko tinggi sehingga kemungkinan bangkrut sangat besar dan berpotensi besar mengalami kebangkruta

The Beam Conditions Monitor of the LHCb Experiment

The LHCb experiment at the European Organization for Nuclear Research (CERN) is dedicated to precision measurements of CP violation and rare decays of B hadrons. Its most sensitive components are protected by means of a Beam Conditions Monitor (BCM), based on polycrystalline CVD diamond sensors. Its configuration, operation and decision logics to issue or remove the beam permit signal for the Large Hadron Collider (LHC) are described in this paper.Comment: Index Terms: Accelerator measurement systems, CVD, Diamond, Radiation detector

Penambahan Auksin Dan Sitokinin Terhadap Pertumbuhan Tunas Dan Akar Gaharu (Aquilaria Malaccensis Lamk) Secara in Vitro in Vitro Addition of Auxin and Cytokinin to Growth of Sshoot and Root of Gaharu (Aquilaria Malaccensis Lamk)

Gaharu (Aquilaria malaccensis L) is one of the non timber forest products (HHBK) has high-value commercial. The high value caused the demand for commodities is increasing every year. But it is inversely proportional to its availability in nature. This research aims to determine the best concentration of the addition of NAA, BAP and the combination between the NAA and BAP on growth of root and shoot of gaharu. The benefits of this research are expected to be a reference in the provision of seedlings with vegetative reproduction in agarwood technique of tissue culture, to support the procurement activities of the seeds in a sufficient amount of a good quality in a relatively short time, and the resulting seedlings were uniform. The methods used factorial experimental design of Randomized complete (RAL) consisting of two factors and three times in Deuteronomy. NAA factor consists of five degrees of treatment i.e. N0 = 0 mg/l, N1 = 1 mg/l, N2 = 2 mg/l, N3 = 3 mg/l and N4 = 4 mg/l, whereas the factor of BAP is also composed of five degrees of concentration i.e. B0 = 0 mg/l, B1 = 0.5 mg/l, B2 = 1 mg/l, B3 = 1.5 mg/l and B4 = 2 mg/l with three times the replay so that required 75 eksplan gaharu. The results showed the best NAA concentration in the added of shoots with a concentration of 0 mg/l NAA, while concentration of 3 mg/l NAA was the best concentration of length the shoots and growth added root gaharu. The best concentration of BAP on shoot length and added long shoots are concentration of 0,5 mg/l BAP, while concentration of 0 mg/l BAP is the best concentration of the growth roots gaharu. Key words : Naphthalene acetic acid, benzyl amino purine, growth hormone, subcultures and aquilaria malaccensis

In vitro Antimicrobial Assessment of Lepidium sativum L. Seeds Extracts

Abstract: The antimicrobial activity of the petroleum ether, methanol and water extracts of Lepidium sativum seed extracts against six opportunistic pathogens namely Staphylococcus aureus, Escherichia coli, Klebsiella pneumonae, Proteus vulgaris, Pseudomonas aeruginosa and one fungus Candida albicans was assessed using the concentrations of 2.5, 5 and 10%. The antimicrobial activity of plant seeds extracts were compared with that of Gentamicin or Ketoconzol, as reference antibiotics. The petroleum ether extract of Lepidium sativum seeds in different concentrations (2.5-5-10%) were found to be active antimicrobials against all the test microorganisms with a strong antifungal activity at the concentration 2.5 and 10%. At the concentration of 5%, the methanolic extract of this plant had no activity against Candida albicans. Staphylococcus aureus and Candida albicans were resistant to 2.5 and 5% water extracts, whereas the latter was also resistant to 5% methanolic extract. The antimicrobial activity of Gentamicin and Ketoconzol against the same test microorganisms was compared with that of the extracts of L. sativum seeds

Why NERICA is a successful innovation for African farmers

This paper responds to ‘Funding international agricultural research and the need to be noticed: a case study of NERICA rice’ by Stuart Orr, James Sumberg, Olaf Erenstein and Andreas Oswald, published in this issue of Outlook on Agriculture. In summary, the article by Orr et al, based on an internal WARDA document written in November 2003 and augmented with results from Internet searches, is outdated and does not seem to be fair, objective or useful. We invite the authors to visit WARDA or any of its partners in Sub-Saharan Africa for evidence of the impact of NERICA varieties or the other improved varieties and technologies that have been developed and disseminated by WARDA in recent years

Toxicological Aspects of Cola acuminata Nut Extracts

Abstract: The multipurpose medicinal plant, Cola acuminata, was chosen for this investigation. Prominent effects on body weight and weight gain was observed. The toxicity on liver, kidney and heart was correlated with changes in the activity of Aspartate Transaminase (AST) and Alanine Transaminase (ALT), and the concentration of cholesterol, albumin and urea in serum. There was an increase in the neutrophils and decrease in lymphocytes in the blood of all the tested groups and an increase of WBC of two groups only. Cytoplasmic fatty vacuolation or necrosis of the centrilobular hepatocytes catarrhal enteritis with minute erosions of the intestinal epithelium with lymphocytic infiltration in the lamina propria and hemosidrin deposition, shrinkage of the glomerular tufts and dilatation of the proximal convoluted tubules were also seen. In group 3 there were lymphocytic infiltrations, glomerular packing, degeneration or necrosis of the epithelial cells of the renal convoluted tubules. No significant lesions were observed in the heart of the test rats. The vital organs of the control rats remained healthy