Distribution of clones among hosts for the lizard malaria parasite Plasmodium mexicanum

Background Malaria parasites reproduce asexually, leading to the production of large numbers of genetically identical parasites, here termed a clonal line or clone. Infected hosts may harbor one or more clones, and the number of clones in a host is termed multiplicity of infection (MOI). Understanding the distribution of parasite clones among hosts can shed light on the processes shaping this distribution and is important for modeling MOI. Here, I determine whether the distribution of clones of the lizard malaria parasite Plasmodium mexicanum differ significantly from statistical distributions commonly used to model MOI and logical extensions of these models. Methods The number of clones per infection was assessed using four microsatellite loci with the maximum number of alleles at any one locus used as a simple estimate of MOI for each infection. I fit statistical models (Poisson, negative binomial, zero-inflated models) to data from four individual sites to determine a best fit model. I also simulated the number of alleles per locus using an unbiased estimate of MOI to determine whether the simple (but potentially biased) method I used to estimate MOI influenced model fit. Results The distribution of clones among hosts at individual sites differed significantly from traditional Poisson and negative binomial distributions, but not from zero-inflated modifications of these distributions. A consistent excess of two-clone infections and shortage of one-clone infections relative to all fit distributions was also observed. Any bias introduced by the simple method for estimating of MOI did not appear to qualitatively alter the results. Conclusions The statistical distributions used to model MOI are typically zero-truncated; truncating the Poisson or zero-inflated Poisson yield the same distribution, so the reasonable fit of the zero-inflated Poisson to the data suggests that the use of the zero-truncated Poisson in modeling is adequate. The improved fit of zero-inflated distributions relative to standard distributions may suggest that only a portion of the host population is located in areas suitable for transmission even at small sites (<1 ha). Collective transmission of clones and premunition may also contribute to deviations from standard distributions.

Rural Tourism Product Planning "Nepal Van Java", Dusun Butuh, Magelang Regency

Nepal Van Java is a tourism attraction that offers the beauty of local residences in Mount Sumbing slope located in Dusun Butuh, Magelang. According to a simple calculation of average visits up to a thousand visitors in one day, Nepal Van Java has a high visitors number according to a simple estimate of average visits. However, at this time, there are not many rural tourism products offered by Nepal Van Java because this destination is still in the planning stage where there is no planning for rustic tourism products. The purpose of this paper is to describe the planning process related to the village tourism product. Qualitative research methods have applied to this research, resulting in an understanding of the actual condition of village tourism products. Detailed planning related to Nepal Van Java tourism products includes planning on facilities, transportation systems, and introduction of visitors, with the idea of focusing on optimizing agricultural resources as agrotourism, potential aids for farm stays, and culture.

Direct fast estimator for recombination frequency in the F2 cross

In this short note, a new unbiased maximum-likelihood estimator is proposed for the recombination frequency in the F2 cross. The estimator is much faster to calculate than its EM algorithm equivalent, yet as efficient. Simulation studies are carried to illustrate the gain over another simple estimate proposed by Benito & Gallego (2004).

A New Approach for Extreme Proportion Calculation: Median Estimate and Its Application to Evaluate Performance of HIV Assays With 100% Test Sensitivity or Specificity

BackgroundIn the evaluation of performance of HIV assays, extreme sample proportions often occur, with test sensitivity and/or specificity of 100%, which making it challenging to assess the assays accuracies. To overcome these challenges, we propose using median estimate as an evaluation indicator for such testing.MethodsBased on the principles of binomial distribution and confidence interval, median estimate was defined as \(p={0.5}^{\frac{1}{n}}\), which means that, when the sample size n is equal to the event number x, namely the sample proportion (e.g., test sensitivity) is 100%, the 50th percentile (median) of p (the estimate of population proportion) is \({0.5}^{\frac{1}{n}}\). After demonstrating the mathematical proof of the median estimate, the key programming commands of commercial software SAS and free software R were given. Subsequently, we developed an Excel-based calculation tool that allows users to fill in data in an Excel sheet without writing any program. Six cases of HIV screening and diagnostic tests and HIV infections incidence data were selected from related articles and World Health Organization reports published between 2009 and 2020.ResultsThe median estimates, which were proved in the range from \(\frac{n-1}{n}\) to 1 and within the confidence interval range, showed statistical plausibility. Six HIV testing cases were presented to illustrate its application and elaborate on the relationship between the median estimate and the conventional simple estimate. These cases demonstrate that, when extreme proportions occurred (i.e., false positive and/or false negative in testing were zero), the conventional simple estimates of sensitivity, specificity, positive predictive value, and negative predictive value were 100% regardless of the sample size and prevalence. In contrast, the corresponding median estimates varied depending on the sample size and prevalence.ConclusionsAs evaluation indicators of HIV assays with extreme proportions, median estimates were more effective than conventional simple estimates. However, simple estimates objectively expressed the results of HIV testing. Because the correlation between median estimates and simple estimates was seamless, the two types of indicators were complementary in the evaluation of testing with extreme proportions. Hence, using both types of estimates could help evaluate HIV assays with extreme proportions more comprehensively.

Potential role of irreversible moist processes in modulating tropical cyclone surface wind structure

Tropical cyclone (TC) wind structure is important for its intensity change and induced damage, but its modulating factors remain to be explored. A heat-engine-based surface wind structure parameter α, reflecting TC’s relative compactness, is introduced and derived based on an entropy budget framework. We found that α is modulated by three key parameters: the thermodynamic efficiency ϵPI in potential intensity theory, the Carnot efficiency ϵC of the system, and the degree of irreversibility αirr of the system. A higher αirr contributes to a larger α and a lower heat engine efficiency. An expression linking TC intensity and compactness also emerges under this framework. Idealized simulations of a typical moist TC (CTL), a dry (DRY) and a moist reversible TC (REV, in which hydrometeors do not fall out) evinced that the significantly higher αirr in CTL, due to irreversible entropy productions from precipitation dissipation, water vapor diffusion and irreversible phase changes, contributes to its much larger compactness compared to DRY and REV. The study illustrates the importance of irreversible entropy production processes in modulating TC surface wind field. Simple estimate suggests that α will increase due to a hypothesized increased αirr with warming because of increased water content. This indicates that TCs will become more compact in a warmer climate.

HOMOMORPHIC OPERATIONS WITHIN IDEAL LATTICE BASED ENCRYPTION SYSTEMS

By 2009 the first system of fully homomorphic encryption had been constructed, and it was thought-provoking for many future works based on it. Instead of legacy encryption systems which depend on sharing a key (public or private) among endpoints involved in exchanging en encrypted message the fully homomorphic encryption can keep service without depending on shared keys and does not necessarily need to access the content. Such property allows any third party to operate on the encrypted data without decrypting it in advance. In this work, the possibility of using the ideal lattices for the construction of homomorphic operations is researched with a detailed level of math.The paper represents the analysis method based on the primitive of a union of ideals in lattice space. A segregated analysis between homomorphic and security properties is the advantage of this method. The work will be based on the analysis of generalized operations over ciphertext using the concept of the base reducing element which shares all about the method above. It will be shown how some non-homomorphic encryption systems can be supplemented by homomorphic operations which invoke different parameters choosing. Thus such systems can be decomposed from ciphertext structure to decryption process which will be affected by separately analyzed base reduction elements. Distinct from the encryption scheme the underlying math can be used to analyze only the homomorphic part, particularly under some simplifications. The building of such ideal-based ciphertext is laying on the assumption that ideals can be extracted further. It will be shown that the “remainder theorem” can be one of the principal ways to do this providing a simple estimate of an upper bound security strength of ciphertext structure.

Space radar terrain survey and the joint flight of a spacecraft pair

The paper considers the concept of space radar monitoring complex performing Earth observation by two spacecrafts according to the technology of synthesized aperture in an interferometry scheme that allows obtaining a global high-precision digital model of the Earth’s relief. The first key problem when creating the complex is the development of an algorithm for determining the heights of the resulting image relative to the relativity surface. Unlike the traditional interferometer scheme using angular coordinates, radar gives the current coordinates of all points involved in the measurement scheme. This allows new algorithm using the difference between two space phase measurements of the downrange to the same surface element to be proposed. Both measurements are performed from two points of common position, spaced apart and representing the interferometry base. As a result, a simple estimate of the potential accuracy of altitude measurement and conditions of its implementation required for the structural scheme of space interferometry are obtained. The second key problem is the arranging coordinated kinematics of the flight of two spacecrafts, forming the base of the space interferometer with the orientation and dimensions that provide the necessary accuracy of altitude measurement. It is shown that both problems are systemically interrelated and the selection of principal solutions to optimize the complex as a whole requires simultaneous consideration and interdisciplinary coordination of the requirements determined by the specifics of each of the two problems. The technique for preliminary project evaluation of results obtained from the orbital group, visually representing all the relationships between individual characteristics of key problem areas of the complex and output target indicators of its work is proposed. The characteristics of the passive flight of spacecraft pair and the conditions for the obtaining high-quality interferometer measurement are considered. It is shown that these conditions are ensured only for a certain part of the orbit, resulting in decreasing efficiency of using the orbital group flight time, and the global survey of the planet relief takes about a year. In this context the possibility of using a small radial thrust applied for a long enough time exceeding a day is shown. As a result, the measurement conditions are stabilized, and the duration of the global survey of the planet relief is reduced to a few months. In addition, the efficiency of using the flight time of the orbital group increases, which allows performing Earth sounding using other possible programs.

Loss of toroidal magnetic flux by emergence of bipolar magnetic regions

The polarity of the toroidal magnetic field in the solar convection zone periodically reverses in the course of the 11/22-year solar cycle. Among the various processes that contribute to the removal of “old-polarity” toroidal magnetic flux is the emergence of flux loops forming bipolar regions at the solar surface. We quantify the loss of subsurface net toroidal flux by this process. To this end, we determine the contribution of an individual emerging bipolar loop and show that it is unaffected by surface flux transport after emergence. Together with the linearity of the diffusion process this means that the total flux loss can be obtained by adding the contributions of all emerging bipolar magnetic regions. The resulting total loss rate of net toroidal flux amounts to 1.3 × 1015 Mx s−1 during activity maxima and 6.1 × 1014 Mx s−1 during activity minima, to which ephemeral regions contribute about 90 and 97%, respectively. This rate is consistent with the observationally inferred loss rate of toroidal flux into interplanetary space and corresponds to a decay time of the subsurface toroidal flux of about 12 years, also consistent with a simple estimate based on turbulent diffusivity. Consequently, toroidal flux loss by flux emergence is a relevant contribution to the budget of net toroidal flux in the solar convection zone. The consistency between the toroidal flux loss rate due to flux emergence and what is expected from turbulent diffusion, and the similarity between the corresponding decay time and the length of the solar cycle are important constraints for understanding the solar cycle and the Sun’s internal dynamics.