Electric feedback cooling of single charged nanoparticles in an optical trap

We demonstrate feedback cooling of the center-of-mass motion of single charged nanoparticles to millikelvin temperatures in three dimensions via applying oscillating electric fields synchronized to their optically observed motion. The observed motional temperatures at weak feedback agree with a simple model and allow us to estimate the charge number of trapped nanoparticles. The agreement between our model and experiments is confirmed by independent measurements of the charge numbers based on a shift in the oscillation frequency induced by a constant electric field. The demonstrated temperature of below 10 mK at $4 \times 10^{-3}$ Pa is lower than that with the conventional optical cooling approach at this pressure by one to two orders of magnitude. Our results form the basis of manipulating cold charged nanoparticles and paves the way to quantum mechanical studies with trapped nanoparticles near their ground state.Comment: 6 pages, 5 figure

Evaluasi Potensi Kecap Manis sebagai Pembawa Fortifikan NaFeEDTA: Tinjauan Pengaruh Asupan Kecap Kedelai Manis Hasil Fortifikasi terhadap Peningkatan Bioavailabilitas Zat Besi Fortifikan

Pengaruh kecap manis sebagai makanan pembawa terhadap peningkatan bioavailabilitas zat besi fortifikan �aFeEDTA, dievaluasi secara in vivo, untuk mengetahui potensi kecap manis sebagai pembawa fortifikan tersebut. Bioavailabilitas ditentukan pada tikus Sprague-Dawley, menggunakan metoda deplesi-replesi hemoglobin. Selama periode replesi, ti- kus yang sebelumnya dibuat anemia, diberi asupan NaFeEDTA (0,35 mg Fe/ekor/hari) sebagai sumber zat besi tunggalselama 14 hari, dengan kecap sebagai pembawa fortifikan. Volume asupan kecap bervariasi, dari 0,0 sampai dengan0,7 mL kecap/ekor/hari. Sebagai pembanding, digunakan sumber zat besi berupa fortifikan standar FeSO .7H O (0,3542mg Fe/hari) dengan H O sebagai pembawa. Bioavailabilitas zat besi dinyatakan sebagai nilai hemoglobin regenerationefficiency (HRE). Volume asupan kecap yang menghasilkan bioavailabilitas yang sama dengan standar FeSO .7H O,42digunakan dalam percobaan selanjutnyanya. Percobaan selanjutnya dilakukan untuk mengevaluasi bioavailabilitas zatbesi NaFeEDTA dengan dosis asupan yang bervariasi (dari 0,175 sampai dengan 1,40 mg Fe/ekor/hari), namun dengan volume pembawa yang tetap (0,2 mL/ekor/hari). Pembawa berupa kecap manis atau H O, sebagai kontrol. Sebagai standar, dipakai FeSO .7H O (0,35 mg Fe/ekor/hari), dengan H O sebagai pembawa. Bioavailabilitas zat besi diten-422tukan dengan metoda deplesi-replesi hemoglobin dan dinyatakan sebagai nilai HRE, absorpsi, dan retensi zat besi. Hasil penelitian menunjukkan bahwa kecap kedelai manis terbukti potensial sebagai pembawa fortifikan �aFeEDTA. Asupan 0,2 mL kecap manis/ekor/hari dapat menghasilkan HRE zat besi fortifikan �aFeEDTA yang sama besar den- gan HRE fortifikan standar. Dibanding dengan kontrol (H O), kecap sebagai makanan pembawa mampu menghasilkanHRE, absorpsi, dan retensi zat besi yang lebih besar. Sementara itu, asupan NaFeEDTA yang makin meningkat dapat menurunkan HRE, A/I, dan R/I yang diperoleh

Kandungan Gizi, Rendemen Tepung, dan Kadar Fenol Total Alpukat (Persea Americana, Mill) Varietas Ijo Panjang dan Ijo Bundar

Penelitian ini bertujuan untuk mengetahui proporsi daging buah, rendemen tepung, kandungan gizi dan fenol total alpukat varietas Ijo Panjang dan Ijo Bundar. Pemilihan kedua varietas tersebut karena merupakan varietas unggul dan direkomendasikan untuk dikembangkan di Indonesia. Kandungan, air, karbohidat, protein, lemak dan abu dilakukan dengan analisis proksimat (AOAC), kandungan vitamin A dan E dengan metode spektrofotometri dan vitamin C dengan metode titrasi, analisis mineral dengan metode AAS. Total fenol dianalisis dengan metode Folin-Ciocalteu. Hasil penelitian menunjukan bahwa proporsi daging buah, kadar air, seng varietas Ijo Panjang lebih tinggi dibandingkan Ijo Bundar. Rendemen tepung alpukat lebih tinggi pada varietas Ijo Bundar. Kandungan protein, lemak, abu, vitamin (A,E dan C), mineral (Fe, Na, K, P) lebih tinggi pada varietas Ijo Bundar. Kandungan magnesium dan mangan tidak terdapat perbedaan signifikan kedua varietas. Fenol total daging buah dan tepung alpukat lebih tinggi pada varietas Ijo Bundar dibandingkan Ijo Panjang

Sifat Prooksidatif Fortifikan NaFeEDTA Dan Fe-SULFAT Pada Kecap Hasil Fortifikasi

Iron in iron-fortified soy sauce may have oxidative effect in both oil and amino acids or protein component. In order to evaluate the possible oxidative properties of both NaFeEDTA and FeSO fortificants, a study of oxidation in soy sauce fortified with the fortificants was conducted. Level of fortificant was 266 mg Fe/L of soy sauce. The extent of oxidation was measured by the level of peroxide value and TBARS value of oil component of fortified soy sauce, as well as car- bonyls content of soy sauce model. The effect of H O addition on level of oxidation was also evaluated. It was found that in soy sauce fortified with either NaFeEDTA or FeSO , the fortificants did not promote oxidation of oil and amino acids components. However, addition of H O made peroxide value, TBARS value, and carbonyls content of fortified samples increased

Sifat Prooksidatif Fortifikan NaFeEDTA, Dengan Kecap Kedelai Manis Sebagai Makanan Pembawa, Dalam Sistem Biologis (Tikus)

In vivo study about the effect of NaFeEDTA fortificant in sweet soy sauce on TBARS value of plasma and liver, as well as on histopathologic changes of liver, intestine, and stomach of Sprague Dawley rats was conducted. The oxida- tive properties were determined using hemoglobin depletion-repletion method. During 42 days of repletion periode, iron-depleted rats were fed iron-free diet. NaFeEDTA was ingested in varied dosage, i.e. from 0.175 to 1.4 mg Fe/day for each rat. Sweet soy sauce H O (0.2 mL/day) was used as fortification vehicle and H O (0.2 mL/day) as a control.22FeSO .7H O fortificant (0.35 mg Fe/day, with H O as vehicle) was used as reference standard. At the end of the reple-422tion period, TBARS value of either plasma or liver was analized. The histopathologic changes of liver, intestine, and stomach were also evaluated. The data showed that NaFeEDTA fortificant in sweet soy sauce had no effect on TBARS value of plasma, but it resulted in increased TBARS value of liver. The histopathologic data showed that NaFeEDTA intake up to 0.35 mg Fe/day did not result in histopathologic changes of liver, intestine, and stomach, as well

Activation of intact bacteria and bacterial fragments mixed with agar as cloud droplets and ice crystals in cloud chamber experiments

Abstract. Biological particles, including bacteria and bacterial fragments, have been of much interest due to the special ability of some to nucleate ice at modestly low temperatures. This paper presents results from a recent study conducted on two strains of cultivated bacteria which suggest that bacterial fragments mixed with agar, and not whole bacterial cells, serve as cloud condensation nuclei (CCN). Due to the absence of whole bacteria cells in droplets, they are unable to serve as ice nucleating particles (INPs) in the immersion mode under the experimental conditions. Experiments were conducted at the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) cloud chamber at the Karlsruhe Institute of Technology (KIT) by injecting bacteria-containing aerosol samples into the cloud chamber and inducing cloud formation by expansion over a temperature range of −5 to −12 °C. Cloud droplets and ice crystals were sampled through a pumped counterflow virtual impactor inlet (PCVI) and their residuals were characterized with a single particle mass spectrometer (miniSPLAT). The size distribution of the overall aerosol was bimodal, with a large particle mode composed of intact bacteria and a mode of smaller particles composed of agar mixed with bacterial fragments that were present in higher concentrations. Results from three expansions with two bacterial strains indicate that the cloud droplet residuals had virtually the same size distribution as the smaller particle size mode and had mass spectra that closely matched those of agar and bacterial fragments. The characterization of ice residuals that were sampled through an ice-selecting PCVI (IS-PCVI) also shows that the same particles that activate to form cloud droplets, bacteria fragments mixed with agar, were the only particle type observed in ice residuals. </jats:p

Experimental Signature of Medium Modifications for rho and omega Mesons in the 12 GeV p + A Reactions

The invariant mass spectra of e+e- pairs produced in 12-GeV proton-induced nuclear reactions are measured at the KEK Proton-Synchrotron. On the low-mass side of the omega meson peak, a significant enhancement over the known hadronic sources has been observed. The mass spectra, including the excess, are well reproduced by a model that takes into account the density dependence of the vector meson mass modification, as theoretically predicted.Comment: 4 pages, 3 figures, Version accepted for Physical Review Lette