Narrow Results

The distribution of elements in human spinal cord was investigated on unfixed frozen cord material using PIXE technique. Distribution of Cu, Zn and Fe were not uniform in the cross section of the spinal cord and concentrations of these elements were higher in the anterior gray horn than in the other areas, while K and Cl distributed uniformly. The content of K changed along the spinsl cord from the cervical to the lumbar level. These findings are discussed in relation to current understanding of the physiology of the spinal cord.

Soybean is one of the major crops in the world as a source of protein. Spatial distribution of elements in bean sprout, soybean seedling, was determined by Particle Induced X-ray Emission (PIXE) analysis to investigate their transfer in the growth. Soybeans were germinated in a dark box at 25~26ºC using pure water without any mineral supplement. After 20hr, 40hr, 65hr and 137hr, the seedlings were harvested and each sprout was separated into cotyledons, hypocotyls, leaves and root. Each part of bean sprout was freeze-dried and applied to PIXE analysis. It was observed that K, Mn, Fe, Cu and Zn moved from the cotyledons and the primary root to the hypocotyls and the 1st leaf, while Ca in the seed hardly moved to other part.

Mate is a kind of tea popular in Central and South America. Trace elements contained in two types of Mate. green Mate and roast Mate. obtained from various districts were determined using PIXE technique comparing the results with those of other teas. Contents of Ca. Mn and Zn in Mate leaf were higher than those of the other tea leaves. Ca and Mn were exuded more easily from the Mate leaves than from the other tea leaves. Exudation amount of Zn was larger in the green Mate than in the roast Mate. It was suggested that Mate is a better supplier of trace elements than other teas.

Selenium (Se) concentrations in plasma, urine, and feces were determined by PIXE analysis before and after intravenous (iv) / oral (po) administration of sodium selenite (a dose equivalent to 2 mg/kg of selenium) to rats. The concentration-time profiles of Se were analyzed by a pharmacokinetic approach. The plasma Se profile after iv injection was biphasic and well-fit to a 2-compartment open model, showing two half lives (t1/2). The first t1/2 was about 0.3 hr and the second t1/2 was 6.9 hrs. The plasma concentration reached almost basal level after about 80 hrs of injection. On the other hand, plasma profiles after po administration showed absorption rate-limiting elimination. The bioavailability of oral sodium selenite (about 49%) and significantly higher amount of fecal Se excretion indicated relatively poor intestinal absorption of sodium selenite, compared to the previously published data. Urinary Se excretion was almost comparable between iv and po groups. The total recovery of the dose excreted in urine and feces was 30 ± 10 % in iv and 56 ± 15 % in po group. The renal excretion was considered to be a major route of Se excretion after absorption. Significant amount of Se that was not fully excreted was noted, suggesting Se distribution or accumulation in organs, together with volatile excretion.

Selenium (Se) concentration-time profiles in plasma and organs including liver, kidney, heart, lung, spleen and brain of rats (Jcl Wister, 9 wks old, n = 32) were investigated after a single intravenous (iv) / oral (po) administration of sodium selenite (dose is equivalent to 2 mg/kg b.w. of Se), The Se concentration was determined by PIXE analysis. Among the investigated biological samples, Se concentration was the highest in the kidney or liver, followed by the heart, lung or spleen, then plasma, and the brain. Se concentrations in these organs were 0.5 to 5 times of plasma Se. The distribution profiles of Se in the organs were dependent on the route of administration. Furthermore, their profiles appeared almost parallel to the plasma Se-concentration in a logarithmic scale. Compared to the Se concentration-time profiles in plasma and organs by the route of administration, po group showed about 1/4-1/2 of the Se concentration in iv group except for kidney. Kidney kept relatively higher concentration of Se, which was similar in the both groups. This may explain our recently published data that urinary excretion was similar in the both groups. The relative oral bioavailability of plasma and each organ was calculated by the ratio of area under the concentration-time curve after oral administration (AUCpo) to AUCiv. Each organ appeared to have their own bioavailability (i.e., liver 39%, kidney 97%, heart 37%, lung 18%, spleen 10%, and brain 72%), where plasma was 46%. These results highly suggested that different Se distribution in organs by the different route of administration was due to the different metabolic profile.

We introduced strong avalanches in the two-dimensional sand-pile and investigated the distributions F(·, L) of their size corresponding to the different system lengths L. Being appropriately scaled, these distributions coincide. The inverse map F^-1 as the function on L sets up the correspondence between the avalanches associated with different L. As to the strong avalanches, with any fixed first argument δ, the map F^-1(δ, L) is proportional to a power function, where the exponent varies from 2 to 3 depending on δ, while F^-1(δ, L) is proportional to L² for the other avalanches.

In this paper, a growing network model with aging mechanism is investigated. Each new node of the network gets attached to the ith existing node with the probability , where k_i is the degree of the ith node and τ_i is its age at time t. β denotes attraction factor and α represents aging intensity. It is found that the network shows scaling behaviors such as scale-free and exponential distribution of degree. Moreover, the phase diagram in the β - α plane is observed, in which there are three regions plotted by two boundaries.

Many patients with chronic hepatitis B (CHB) seek help from traditional Chinese medicine (TCM). TCM treatment is based on syndrome differentiation. This study aimed to investigate the syndrome distribution in populations of CHB patients. The pre-specific search strategy was set, and 93 studies (20,106 participants) were identified by electronic and hand searches. The methodological quality of included studies was assessed. Data on syndrome distribution and correlations between syndromes and severity of CHB, were extracted and analyzed. Forty-seven syndromes were identified under 24 different syndrome diagnosis systems for CHB. The majority of included studies reported Liver Depression and Spleen Deficiency (LDSD) (52.54% of studies) or Liver-Gallbladder Dampness Heat (LGDH)/Dampness-Heat Obstructing Middle Energizer (DHME) (32.20%) as the major syndromes in CHB patients without cirrhosis. Pooled analysis revealed that LDSD and LGDH/DHME accounted for 61.19% of participants without cirrhosis. In addition, Liver-Kidney Yin Deficiency (LKYinD) (40.99%) and Spleen-Kidney Yang Deficiency (SKYangD) (40.43%) syndromes were common in patients with severe CHB. The percentage of patients with Blood Stasis syndrome increased as the disease progressed to cirrhosis (32.09%). To conclude, LDSD and LGDH/DHME syndromes are found in a significant majority of CHB patients, particularly in the early stages. LKYinD, SKYangD and Blood Stasis dominate in patients at more advanced stages. More epidemiological studies of high methodological quality on syndrome distribution in CHB and standardization of syndrome differentiation for CHB are required to confirm the trends indicated by the studies reviewed here; confirming these trends can increase the efficacy of treatment and give guidance to doctors.

By studying the critical properties of a 2D Bose–Einstein condensation (BEC) in traps, we obtain the accurate analytic expressions of transition temperature, condensed fraction, and specific heat. The analytic results fit in fairly well with numerical results. We find that an isotropical potential favors most for condensation to occur. With the aid of Bloch summation, we study the distributions of coordinates and momenta of the system. Some clear physical pictures are presented.

The ubiquitous presence of complexity in nature makes it necessary to seek new mathematical tools which can probe physical systems beyond linear or perturbative approximations. The random matrix theory is one such tool in which the statistical behavior of a system is modeled by an ensemble of its replicas. This paper is an attempt to review the basic aspects of the theory in a simplified language, aimed at students from diverse areas of physics.

In this paper, we analyze a mixture of Lognormal and Log-Logistic distribution. We estimate the parameters of the introduced distribution by using the expectation-maximization (EM) algorithm. Various phenomena in the field of medicine and economy could be modeled by this mixture. In this paper, it is used to construct new mortality model for determining the unisex premium rates in life insurance. The application of the model is illustrated in the case of Serbian population and its advantages are presented in the context of life insurance premium calculation.

The generalized incremental ratio fractional derivative is revised and its main properties deduced. It is shown that in the case of analytic functions, it enjoys some interesting properties like: linearity and causality and has a semi-group structure. Some simple examples are presented. The enlargement of the set of functions for which the group properties of the fractional derivative are valid is done. With this, it is shown that some well-known results are valid in a more general set-up. Some examples are presented.

Gene expression is inherently noisy, implying that the number of mRNAs or proteins is not invariant rather than follows a distribution. This distribution can not only provide the exact information on the dynamics of gene expression but also describe cell-to-cell variability in a genetically identical cell population. Here, we systematically investigate a two-state model of gene expression, a model paradigm used to study expression dynamics, focusing on the effect of feedback on the type of mRNA or protein distribution. If there is no feedback, then the distribution may be bimodal, power-law tailed, or Poisson-like, depending on gene switching rates. However, we find that feedback can tune or change the type of the distribution in each case and tends to unimodalize the distribution as its strength increases. Specifically, positive feedback can change not only a power-law tailed distribution into a bimodal or Poisson-like distribution but also a bimodal distribution into a Poisson-like distribution (implying that stochastic bifurcation can take place). In addition, it can make a Poisson-like distribution become more peaked but does not change the type of this distribution. In contrast to positive feedback, negative feedback has less influence on the shape of the distributions except for the bimodal case. In all cases, the noise-feedback curve used extensively in previous studies cannot well reflect the feedback-induced changes in the shape of distributions. Feedback-induced variations in distribution would be important for cell survival in fluctuating environments.

This work presents a numerical method to color the bifurcation diagram of any discrete map, based on the distribution of the map’s values in its domain. This density-colored diagram reveals information on the uniformity of the map’s value distribution across its domain set, as a bifurcation parameter is increased. This diagram can serve as a complementary visual tool for the analysis of chaotic maps, and can be vital for the application of chaotic dynamics.

Knowledge bases contain specific and general knowledge. In relational database systems, specific knowledge is often represented as a set of relations. The conventional methodologies for centralized database design can be applied to develop a normalized, redundancy-free global schema. Distributed database design involves redundancy removal as well as the distribution design which allows replicated data segments. Thus, distribution design can be viewed as a process on a normalized global schema which produces a collection of fragments of relations from a global database. Clearly, not every fragment of data can be permitted as a relation. In this paper, we clarify and formally discuss three kinds of fragmentations of relational databases, and characterize their features as valid designs, and we introduce a hybrid knowledge fragmentation as the general case. For completeness of presentation, we first show an algorithm for the validity test of vertical fragmentations of normalized relations, and then extend it to the more general case of unbiased fragmentations.

This paper includes the experimental measurements for the angular distributions of ¹⁶O ion beam elastically scattered by ¹⁶O nuclei at energies 20, 24 and 28 MeV. The experimental results were analyzed within the framework of both the optical model using different complex potential and the double folding (DF) potential obtained with different density-dependent nucleon–nucleon interactions which give the corresponding values of the nuclear incompressibility K in the Hartree–Fock calculation of nuclear matter. The agreement between the experimental results and the theoretical predictions in the whole angular range is fairly good. In DF calculations, the obtained normalization coefficient N_r is in the range 0.833–1.07.

We argue that $p_T$ distribution data from the LHC on the invariant differential yield of the charged primary particles in $pp$ collisions at $\sqrt{s}=0.9\mathrm{\text{TeV}},2.76\mathrm{\text{TeV}},7\mathrm{\text{TeV}}$ and in Pb–Pb collisions at $\sqrt{s_{NN}}=2.76$TeV with six centrality bins contains several $p_T$ regions with special properties. These distributions were analyzed by fitting the data with exponential functions. We conclude that the regions reflect features of fragmentation and hadronization of partons through the string dynamics. The nuclear transparency results in negligible influence of the medium in the III region ($p_T>17-20\mathrm{\text{GeV/c}}$), which has highest $p_T$ values. The effects and changes by the medium start to appear weakly in the II region ($4-6\mathrm{\text{GeV/c}}<p_T<17-20\mathrm{\text{GeV/c}}$) and become stronger in the I region ($p_T<4-6\mathrm{\text{GeV/c}}$). It seems that the II region has highest number of strings. The increase in string density in this region could lead to fusion of strings, appearance of a new string and collective behavior of the partons in the most central collisions. These phenomena can explain anomalous behavior of the Nuclear Modification Factor in the II region. We propose the II region as a possible area of Quark Gluon Plasma formation through string fusion. The first $p_T$ regions are the ones with the maximum number of hadrons and minimum number of strings due to direct hadronization of the low energy strings into two quark systems–mesons.

In this work, we use matrix models to study the problem of strength distributions. This is motivated by noticing near exponential falloffs of strengths in calculated magnetic dipole excitations. We emphasize that the quality of the exponential falloffs depends on the parameters in our matrices, especially the relative size of the couplings to the unperturbed level separations. We also find a dark matrix for which all transitions vanish.

In this work, we extend a previous study of matrix models of strength distributions. We still retain the nearest neighbor coupling mode but we extend the values of the coupling parameter $v$. We consider extremes, from very small $v$ to very large $v$. We first use the same transition operator as before $〈nT(n+1)〉=\mathrm{\text{constant}}(=1)$. For this case, we get an exponential decrease for small $v$, as expected, but we get a phase transition beyond $v$=10, where we get separate exponentials for even $n$ and for odd $n$. We now also consider the dipole choice where $〈nT(n+1)〉=\sqrt{(n+1)}$.

We show some interesting properties of tridiagonal and pentadiagonal matrices in the weak coupling limits. In the former case of this limit, the ground state wave function amplitudes are identical to the Taylor expansion coefficients of the exponential function e${}^{(-\frac{v}{e})}$. With regards to transition rates, a dip in the pentadiagonal case which is not present in the tridiagonal case is explained. An intimate connection between energy denominators and exponential behavior is demonstrated.