133 research outputs found
Drought Analysis for 2007-2008 Agricultural Year of Turkey
Drought is among the most significant natural disasters and has severe economical, social and environmental impacts. It is somehow different from the other natural disasters since it is hard to determine exact start and end dates of drought. Drought gradually increases its severity and may keep its effects for years after the end of drought. Effects of drought is initially observed in agriculture and diffused gradually into waterrelated sectors. The recent global drought and utilization of agricultural crops for bio-fuel production has created significant problems in food supply. For instance, as a result of the drought experienced in the year of 2007, wheat production was not sufficient. Beside this, consumption increased for bio-fuel production and wheat prices in international markets increased by 3 folds. These problems observed in basic agricultural crops like maize and rice has brought forward the significance of continuous drought monitoring and analysis. In this study, the drought experienced in 2007-2008 Agricultural Year of Turkey was analyzed and contributions were tried to be made for future production activities. The drought was evaluated by using Standardized Precipitation Index (SPI), Percent of Normal Index (PNI) and the analyses of precipitation and temperature analysis
Protecting the operation from general and residual errors by continuous dynamical decoupling
We study the occurrence of errors in a continuously decoupled two-qubit state
during a quantum operation under decoherence. We consider a
realization of this quantum gate based on the Heisenberg exchange interaction,
which alone suffices for achieving universal quantum computation. Furthermore,
we introduce a continuous-dynamical-decoupling scheme that commutes with the
Heisenberg Hamiltonian to protect it from the amplitude damping and dephasing
errors caused by the system-environment interaction. We consider two
error-protection settings. One protects the qubits from both amplitude damping
and dephasing errors. The other features the amplitude damping as a residual
error and protects the qubits from dephasing errors only. In both settings, we
investigate the interaction of qubits with common and independent environments
separately. We study how errors affect the entanglement and fidelity for
different environmental spectral densities.Comment: Extended version of arXiv:1005.1666. To appear in PR
Quantum Correlations and Coherence in Spin-1 Heisenberg Chains
We explore quantum and classical correlations along with coherence in the
ground states of spin-1 Heisenberg chains, namely the one-dimensional XXZ model
and the one-dimensional bilinear biquadratic model, with the techniques of
density matrix renormalization group theory. Exploiting the tools of quantum
information theory, that is, by studying quantum discord, quantum mutual
information and three recently introduced coherence measures in the reduced
density matrix of two nearest neighbor spins in the bulk, we investigate the
quantum phase transitions and special symmetry points in these models. We point
out the relative strengths and weaknesses of correlation and coherence measures
as figures of merit to witness the quantum phase transitions and symmetry
points in the considered spin-1 Heisenberg chains. In particular, we
demonstrate that as none of the studied measures can detect the infinite order
Kosterlitz-Thouless transition in the XXZ model, they appear to be able to
signal the existence of the same type of transition in the biliear biquadratic
model. However, we argue that what is actually detected by the measures here is
the SU(3) symmetry point of the model rather than the infinite order quantum
phase transition. Moreover, we show in the XXZ model that examining even single
site coherence can be sufficient to spotlight the second-order phase transition
and the SU(2) symmetry point.Comment: 8 pages. 5 figure
Defense styles from the perspective of affective neuroscience
To our knowledge, no study has been carried out to observe which subcortical basic affective systems are related to which defense styles. Such a perspective may have the potential to reveal how defenses may interact with subcortical primary emotional systems (PES) and how they contribute to affect regulation. We aimed to analyze the relationship of immature, neurotic, and mature defenses with basic subcortical affects (CARE, PLAY, SEEK, SADNESS, FEAR, ANGER) within an affective neuroscientific perspective. In addition, we sought to explore the effect of psychiatric disorders in relation to PES and defenses, and observe gender effects, if any. The sample consisted of 703 university students, recruited online. The materials included the Turkish translations of the Affective Neuroscience Personality Scales (ANPS) and the Defense Style Questionnaire (DSQ). The correlations between ANPS and DSQ showed that the immature defenses increase as all negative emotions increase, whereas mature defenses increase as all positive emotions (except CARE) increase and all negative affects decrease (except ANGER). On the other hand, as neurotic defenses increase, CARE, FEAR and SADNESS simultaneously increase. Subjects who reported the presence of psychiatric disorders also reported higher FEAR, SADNESS, ANGER accompanied by higher immature defenses. Finally, male subjects reported higher immature defenses, whereas the females reported higher neurotic defenses, accompanied by higher CARE, SEEK, SADNESS, FEAR, and slightly lower PLAY. Investigating defenses through the lens of affective neuroscience offers the opportunity to link the abstract concept of defenses to increasingly well-understood neurobiology
Biofortification and Localization of Zinc in Wheat Grain
Zinc (Zn) deficiency associated with low dietary intake is a well-documented public health problem, resulting in serious health and socioeconomic problems. Field experiments were conducted with wheat to test the role of both soil and foliar application of ZnSO4 in Zn concentration of whole grain and grain fractions (e.g., bran, embryo and endosperm) in 3 locations. Foliar application of ZnSO4 was realized at different growth stages (e.g., stem elongation, boot, milk, dough stages) to study the effect of timing of foliar Zn application on grain Zn concentration. The rate of foliar Zn application at each growth stage was 4 kg of ZnSO4 3 7H2O ha-1. Laser ablation (LA)-ICP-MS was used to follow the localization of Zn within grain. Soil Zn application at a rate of 50 kg of ZnSO4 3 7H2O ha-1 was effective in increasing grain Zn concentration in the Zn-deficient location, but not in the locations without soil Zn deficiency. In all locations, foliar application of Zn significantly increased Zn concentration in whole grain and in each grain fraction, particularly in the case of high soil N fertilization. In Zn-deficient location, grain Zn concentration increased from 11 mg kg-1 to 22 mg kg-1 with foliar Zn application and to 27 mg kg-1 with a combined application of ZnSO4 to soil and foliar. In locations without soil Zn deficiency, combination of high N application with two times foliar Zn application (e.g., at the booting and milk stages) increased grain Zn concentration, on average, from 28 mg kg-1 to 58 mg kg-1. Both ICP-OES and LA-ICP-MS data showed that the increase in Zn concentration of whole grain and grain fractions was pronounced when Zn was sprayed at the late growth stage (e.g., milk and dough). LA-ICP-MS data also indicated that Zn was transported into endosperm through the crease phloem. To our knowledge, this is the first study to show that the timing of foliar Zn application is of great importance in increasing grain Zn in wheat, especially in the endosperm part that is the predominant grain fraction consumed in many countries. Providing a large pool of Zn in vegetative tissues during the grain filling (e.g., via foliar Zn spray) is an important practice to increase grain Zn and contribute to human nutritio
Computational speed-up with a single qudit
Quantum algorithms are known for providing more efficient solutions to
certain computational tasks than any corresponding classical algorithm. Here we
show that a single qudit is sufficient to implement an oracle based quantum
algorithm, which can solve a black-box problem faster than any classical
algorithm. For permutation functions defined on a set of elements,
deciding whether a given permutation is even or odd, requires evaluation of the
function for at least two elements. We demonstrate that a quantum circuit with
a single qudit can determine the parity of the permutation with only one
evaluation of the function. Our algorithm provides an example for quantum
computation without entanglement since it makes use of the pure state of a
qudit. We also present an experimental realization of the proposed quantum
algorithm with a quadrupolar nuclear magnetic resonance using a single
four-level quantum system, i.e., a ququart.Comment: Combined version of arXiv:1403.5861 [quant-ph] and arXiv:1406.3579
[quant-ph
Microcantilever based LoC system for coagulation measurements
In this paper, a microcantilever-based system enabling multiple coagulation tests on the same disposable cartridge is demonstrated. The system consists of independent cartridge and reader unit. The actuation of the nickel cantilevers is conducted remotely with an external electro-coil and remote optical read-out is utilized for sensing. Both Prothrombin Time (PT) and activated Partial Thromboplastin Time (aPTT) tests can be conducted on the same cartridge. The system’s repeatability and accuracy is investigated with standard control plasma samples. The results are concordant with the manufacturer’s datasheet. The architecture of the system and the repeatable results makes the system suitable for Point-of-Care applications.TÜBİTA
Microcantilever based LoC system for coagulation measurements
In this paper, a microcantilever-based system enabling multiple coagulation tests on the same disposable cartridge is demonstrated. The system consists of independent cartridge and reader unit. The actuation of the nickel cantilevers is conducted remotely with an external electro-coil and remote optical read-out is utilized for sensing. Both Prothrombin Time (PT) and activated Partial Thromboplastin Time (aPTT) tests can be conducted on the same cartridge. The system’s repeatability and accuracy is investigated with standard control plasma samples. The results are concordant with the manufacturer’s datasheet. The architecture of the system and the repeatable results makes the system suitable for Point-of-Care applications.TÜBİTA
Effect of molecular and electronic structure on the light harvesting properties of dye sensitizers
The systematic trends in structural and electronic properties of perylene
diimide (PDI) derived dye molecules have been investigated by DFT calculations
based on projector augmented wave (PAW) method including gradient corrected
exchange-correlation effects. TDDFT calculations have been performed to study
the visible absorbance activity of these complexes. The effect of different
ligands and halogen atoms attached to PDI were studied to characterize the
light harvesting properties. The atomic size and electronegativity of the
halogen were observed to alter the relaxed molecular geometries which in turn
influenced the electronic behavior of the dye molecules. Ground state molecular
structure of isolated dye molecules studied in this work depends on both the
halogen atom and the carboxylic acid groups. DFT calculations revealed that the
carboxylic acid ligands did not play an important role in changing the
HOMO-LUMO gap of the sensitizer. However, they serve as anchor between the PDI
and substrate titania surface of the solar cell or photocatalyst. A
commercially available dye-sensitizer, ruthenium bipyridine (RuBpy), was also
studied for electronic and structural properties in order to make a comparison
with PDI derivatives for light harvesting properties. Results of this work
suggest that fluorinated, chlorinated, brominated, and iyodinated PDI compounds
can be useful as sensitizers in solar cells and in artificial photosynthesis.Comment: Single pdf file, 14 pages with 7 figures and 4 table
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