Nanoscale magnetometry using a single spin system in diamond

We propose a protocol to estimate magnetic fields using a single nitrogen-vacancy (N-V) center in diamond, where the estimate precision scales inversely with time, ~1/T$, rather than the square-root of time. The method is based on converting the task of magnetometry into phase estimation, performing quantum phase estimation on a single N-V nuclear spin using either adaptive or nonadaptive feedback control, and the recently demonstrated capability to perform single-shot readout within the N-V [P. Neumann et. al., Science 329, 542 (2010)]. We present numerical simulations to show that our method provides an estimate whose precision scales close to ~1/T (T is the total estimation time), and moreover will give an unambiguous estimate of the static magnetic field experienced by the N-V. By combining this protocol with recent proposals for scanning magnetometry using an N-V, our protocol will provide a significant decrease in signal acquisition time while providing an unambiguous spatial map of the magnetic field.Comment: 8 pages and 5 figure

Inhibition of Intestinal Thiamin Transport in Rat Model of Sepsis.

ObjectivesThiamin deficiency is highly prevalent in patients with sepsis, but the mechanism by which sepsis induces thiamin deficiency is unknown. This study aimed to determine the influence of various severity of sepsis on carrier-mediated intestinal thiamin uptake, level of expressions of thiamin transporters (thiamin transporter-1 and thiamin transporter-2), and mitochondrial thiamin pyrophosphate transporter.DesignRandomized controlled study.SettingResearch laboratory at a Veterans Affairs Medical Center.SubjectsTwenty-four Sprague-Dawley rats were randomized into controls, mild, moderate, and severe sepsis with equal number of animals in each group.InterventionsSepsis was induced by cecal ligation and puncture with the cecum ligated below the cecal valve at 25%, 50%, and 75% of cecal length, defined as severe, moderate, and mild sepsis, respectively. Control animals underwent laparotomy only.Measurements and main resultsAfter 2 days of induced sepsis, carrier-mediated intestinal thiamin uptake was measured using [H]thiamin. Expressions of thiamin transporter-1, thiamin transporter-2, and mitochondrial thiamin pyrophosphate transporter proteins and messenger RNA were measured. Proinflammatory cytokines (interleukin-1β and interleukin-6) and adenosine triphosphate were also measured. Sepsis inhibited [H]thiamin uptake, and the inhibition was a function of sepsis severity. Both cell membrane thiamin transporters and mitochondrial thiamin pyrophosphate transporter expression levels were suppressed; also levels of adenosine triphosphate in the intestine of animals with moderate and severe sepsis were significantly lower than that of sham-operated controls.ConclusionsFor the first time, we demonstrated that sepsis inhibited carrier-mediated intestinal thiamin uptake as a function of sepsis severity, suppressed thiamin transporters and mitochondrial thiamin pyrophosphate transporter, leading to adenosine triphosphate depletion

Kinerja Bundaran Bersinyal Digulis Kota Pontianak

Fully signalized roundabout must meet design criteria which are very different compared to the recommended design for unsignalized roundabout. When traffic flow increases, there is greater probability that traffic queue to occure, that will decrease the operation level of the roundabout and reduce the intersection capacity. In the case of the Digulis Signalized Roundabout, in Pontianak City, the high traffic volume causes problems, at the roundabout and particularly at the signalized intersection. At the roundabout, in C-D weaving direction, the degree of saturation reaches 0,933, while at signalized intersection, at leg A, major traffic direction, Ahmad Yani street, the degree saturation reaches 0,841, which causes long queues, with the length of 148 meters for leg A and 128 meters for leg B. The delay occured is 13.73 pcu.sec 10,64 pcu.sec, at directions A and B, respectively

Kajian Fasilitas Pembatas Kecepatan pada Komplek Perumahan di Kota Pontianak

Alat pengendali kecepatan atau yang lebih dikenal dengan polisi tidur merupakan salah satu alat rekayasa lalu lintas yang berfungsi untuk mengendalikan kecepatan kendaraan yang melintas di suatu ruas jalan, terutama di kawasan Perumahan guna melindungi pejalan kaki, pengendara sepeda, anak – anak maupun lanjut usia.Akan tetapi banyak sekali variasi bentuk yang dibuat oleh masyarakat sehingga menyebabkan alat pengendali kecepatan ini tidak nyaman untuk dilewati oleh pengendara kendaraan. Selain itu, pemasangan alat pengendali kecepatan ini tidak disertakan dengan pemasangan tanda dan rambu sehingga menyebabkan efek kejut pada pengendara. Pada Penelitian ini dilakukan analisis tentang tinggi, sudut kemiringan Speed Bumps, Kenyamanan pengendara kendaraan dan pengamatan pemasangan tanda dan rambu sebagai perlengkapan Speed Bumps pada setiap kompleks yang menjadi lokasi penelitian. Metode Penilitian ini menggunakan metode survei untuk mengambil sampel bentuk Speed Bumps, sebaran kecepatan kendaraan pada kompleks Perumahan yang dipasang Speed Bumps, dan penurunan kecepatan kendaraan saat melewati Speed Bumps setiap kecamatan yang ada di Kotamadya Pontianak Dari hasil penelitian didapatkan variasi tinggi Speed Bumps tertinggi pada lokasi penelitian adalah 13 cm, sedangkan variasi tinggi Speed Bumps terendah adalah 3 cm dengan berbagai variasi kemiringan ≥ 15% dengan bentuk sinusoidal. Kenyamanan berkendara bagi para pengendara tidak begitu menyenangkan, karena berkisar antara 2 – 5 km/jam. Hal ini menunjukkan hasil yang tidak ideal dan dipersulit dengan tidak adanya pemasangan rambu dan markah. Dinyatakan pemasangan Speed Bumps tersebut ideal dan baik apabila memiliki tinggi ≤12 cm dan sudut kemiringan ≤ 15 % serta dilengkapi dengan pemasangan rambu dan tanda sebagai peringatan bagi pengendara kendaraan

Properties of cosmic rays incident in the near-horizontal direction

The Durham 'horizontal spectrograph' Mark II has been used to measure the momentum spectrum and the charge ratio of Cosmic-ray muons in the zenith angle range 82.5 - 90 to about 2000 GeV and the results are based on a sample of 3918 particles. By comparing the measured spectra with those predicted from the measured vertical spectrum, for different values of the K/π ratio, a value of 0.42 ± 0.20 has been derived for the K/π ratio in the muon energy range at production, 100 - 2000 GeV, corresponding to3 5primary energy range of ~3.10(^3) – 10(^5) GeV. When comparison is made with the k/π ratios determined by other indirect methods it is concluded that there is no evidence against a near-constant ratio over the wide primary energy range 10(^2) – 10(^6) covered by all methods and that the average value is 0.35 ± 0.20 over this energy range. The present results confirm the results of other authors on the existence of an appreciable charge excess up to energies of at least a few hundred GeV. The present results suggest that at the largest zenith angles there is a maximum in the charge ratio in the energy region 50 - 100 GeV, a feature which does not confirm the minimum in the same energy region, but at somewhat smaller zenith angles, reported by some other workers. The reason for the appearance of the maximum is not known despite strenuous efforts to explain it. At higher energies, one cannot say, sue to the considerable errors in all the data, that there is disagreement between the present result and other data and neither an increase or decrease in the ration is ruled out. The interaction of the incident particles (hitherto assumed to be muons) has been studied from the point of view of identification of the particles. It is shown that the results can be interpreted in terms of the known electromagnetic interactions of muons and the conclusion arrived at is that there is no evidence for the existence of an appreciable flux of the so-called X – particles that could be contaminating the incident muon beam