Dimension reduction by balanced truncation: Application to light-induced control of open quantum systems

In linear control, balanced truncation is known as a powerful technique to reduce the state-space dimension of a system. Its basic principle is to identify a subspace of jointly easily controllable and observable states and then to restrict the dynamics to this subspace without changing the overall response of the system. This work deals with a first application of balanced truncation to the control of open quantum systems which are modeled by the Liouville-von Neumann equation within the Lindblad formalism. Generalization of the linear theory have been proposed to cope with the bilinear terms arising from the coupling between the control field and the quantum system. As an example we choose the dissipative quantum dynamics of a particle in an asymmetric double well potential driven by an external control field, monitoring population transfer between the potential wells as a control target. The accuracy of dimension reduction is investigated by comparing the populations obtained for the truncated system versus those for the original system. The dimension of the model system can be reduced very efficiently where the degree of reduction depends on temperature and relaxation rate

Formation and interactions of cold and ultracold molecules: new challenges for interdisciplinary physics

Progress on researches in the field of molecules at cold and ultracold temperatures is reported in this review. It covers extensively the experimental methods to produce, detect and characterize cold and ultracold molecules including association of ultracold atoms, deceleration by external fields and kinematic cooling. Confinement of molecules in different kinds of traps is also discussed. The basic theoretical issues related to the knowledge of the molecular structure, the atom-molecule and molecule-molecule mutual interactions, and to their possible manipulation and control with external fields, are reviewed. A short discussion on the broad area of applications completes the review.Comment: to appear in Reports on Progress in Physic

German National Consensus Recommendations on Nutrition and Lifestyle in Pregnancy by the ‘Healthy Start - Young Family Network’

Diet and physical activity before and during pregnancy affect short- andlong-term health of mother and child. The energy needs at the end ofpregnancy increase only by about 10% compared to nonpregnant women. Anexcessive energy intake is undesirable since maternal overweight andexcessive weight gain can increase the risks for a high birth weight andlater child overweight and diabetes. Maternal weight at the beginning ofpregnancy is especially important for pregnancy outcome and childhealth. Women should strive to achieve normal weight already beforepregnancy. Regular physical activity can contribute to a healthy weightand to the health of pregnant women. The need for certain nutrientsincreases more than energy requirements. Before and during pregnancy,foods with a high content of essential nutrients should bepreferentially selected. Supplements should include folic acid andiodine, iron (in case of suboptimal iron stores), the omega-3 fatty aciddocosahexaenoic acid (in case of infrequent consumption of ocean fish)and vitamin D (in case of decreased sun exposure and decreasedendogenous vitamin D synthesis). Pregnant women should not smoke and notstay in rooms where others smoke or have smoked before (passivesmoking). Alcohol consumption should be avoided, since alcohol can harmunborn children

German National Consensus Recommendations on Nutrition and Lifestyle in Pregnancy by the ‘Healthy Start - Young Family Network’

Diet and physical activity before and during pregnancy affect short- andlong-term health of mother and child. The energy needs at the end ofpregnancy increase only by about 10% compared to nonpregnant women. Anexcessive energy intake is undesirable since maternal overweight andexcessive weight gain can increase the risks for a high birth weight andlater child overweight and diabetes. Maternal weight at the beginning ofpregnancy is especially important for pregnancy outcome and childhealth. Women should strive to achieve normal weight already beforepregnancy. Regular physical activity can contribute to a healthy weightand to the health of pregnant women. The need for certain nutrientsincreases more than energy requirements. Before and during pregnancy,foods with a high content of essential nutrients should bepreferentially selected. Supplements should include folic acid andiodine, iron (in case of suboptimal iron stores), the omega-3 fatty aciddocosahexaenoic acid (in case of infrequent consumption of ocean fish)and vitamin D (in case of decreased sun exposure and decreasedendogenous vitamin D synthesis). Pregnant women should not smoke and notstay in rooms where others smoke or have smoked before (passivesmoking). Alcohol consumption should be avoided, since alcohol can harmunborn children

The 3′-Terminal Hexamer Sequence of Classical swine fever virus RNA Plays a Role in Negatively Regulating the IRES-Mediated Translation

The 3′ untranslated region (UTR) is usually involved in the switch of the translation and replication for a positive-sense RNA virus. To understand the 3′ UTR involved in an internal ribosome entry site (IRES)-mediated translation in Classical swine fever virus (CSFV), we first confirmed the predicted secondary structure (designated as SLI, SLII, SLIII, and SLIV) by enzymatic probing. Using a reporter assay in which the luciferase expression is under the control of CSFV 5′ and 3′ UTRs, we found that the 3′ UTR harbors the positive and negative regulatory elements for translational control. Unlike other stem loops, SLI acts as a repressor for expression of the reporter gene. The negative cis-acting element in SLI is further mapped to the very 3′-end hexamer CGGCCC sequence. Further, the CSFV IRES-mediated translation can be enhanced by the heterologous 3′-ends such as the poly(A) or the 3′ UTR of Hepatitis C virus (HCV). Interestingly, such an enhancement was repressed by flanking this hexamer to the end of poly(A) or HCV 3′ UTR. After sequence comparison and alignment, we have found that this hexamer sequence could hypothetically base pair with the sequence in the IRES IIId1, the 40 S ribosomal subunit binding site for the translational initiation, located at the 5′ UTR. In conclusion, we have found that the 3′-end terminal sequence can play a role in regulating the translation of CSFV

Optimal control of ionization processes in NaK; comparison between theory and experiment

We report a good agreement between the shapes of tailored pulses obtained theoretically and experimentally by using the optimal-control theory and the closed-loop learning technique to maximize the ionization yield in NaK. The theoretical pulse shapes are found to be robust regarding the choice of the initial guess. We assign the leading features of the pulse shapes to processes underlying the optimal control and reveal the mechanism which involves an electronic transition followed by a direct two-photon process and sequential one-photon processes at later times. We show that the optimal control not only serves for maximizing the desired yield but also as a tool for the analysis and the identification of the responsible processes

New approaches for electrochemical detection of ascorbic acid

Ascorbic acid, well known as vitamin C, acts as antioxidant, helping the prevention of cell damage caused by free radicals. The paper presents fast methods for detecting ascorbic acid, using differential pulse voltammetry in different designed experiments. There were studied the possibilities of detection using buffer systems with pH 5.8, 7.0, 7.4 and original transducers. Each compound was analysed specifically at the potential indicated by the maximum signal appeared during the electrochemical study. The method could be successfully applied for single compound detection in food and drug samples