Effects of reducing insemination time in human in vitro fertilization and embryo development by using sibling oocytes

PURPOSE: Recent studies showed a beneficial effect of reducing the time of sperm-oocyte interaction on fertilization, division, and implantation rates of the oocytes obtained from randomized patients. In the present study, the effects of reduced insemination time on fertilization and embryo development were evaluated by using sibling oocytes from the same patient. METHODS: A total of 464 oocytes from 36 patients was randomly allocated to be inseminated for either 1 hr (reduced) or 18 hr (regular). RESULTS: Fertilization rates were not significantly different between reduced (135/229; 59%) and regular (150/235; 64%) groups. Cleavage rates and embryo quality were similar in both groups. A total of 135 embryos (73 from the reduced and 62 from the regular group) was transferred to 36 patients. Thirty-four embryos implanted in 18 patients (25.2% implantation and 50.0% pregnancy rates). CONCLUSIONS: Fertilization, cleavage, and embryo development from 1-hr insemination is comparable, not superior, to those from an 18-hr insemination time, which is commonly used in in vitro fertilization programs. These data suggest that reduced insemination time can be used during in vitro fertilization to avoid unnecessarily longer exposure to spermatozoa.     

A hybrid fuzzy MCDM approach to machine tool selection

The selection of the appropriate machine tools for a manufacturing company is one of the important points to achieving high competitiveness in the market. Besides, an appropriate choice of machine tools is very important as it helps to realize full production quickly. Today’s market offers many more choices for machine tool alternatives. There are also many factors one should consider as part of the appropriate machine tool selection process, including productivity, flexibility, compatibility, safety, cost, etc. Consequently evaluation procedures involve several objectives and it is often necessary to compromise among possibly conflicting tangible and intangible factors. For these reasons, multiple criteria decision making (MCDM) has been found to be a useful approach to solve this kind of problem. Most of the MCDM models are basically mathematical and ignore qualitative and often subjective considerations. The use of fuzzy set theory allows incorporating qualitative and partially known information into the decision model. This paper describes a fuzzy technique for order preference by similarity to ideal solution (TOPSIS) based methodology for evaluation and selection of vertical CNC machining centers for a manufacturing company in Istanbul, Turkey. The criteria weights are calculated by using the fuzzy AHP (analytical hierarchy process).     

Static priority scheduling of event-triggered real-time embedded systems

Real-time embedded systems are often specified as a collection of independent tasks, each generating a sequence of event-triggered code blocks. The goal of scheduling tasks in this domain is to find an execution order which satisfies all real-time constraints. Within the context of recurring real-time tasks, all previous work either allowed preemptions, or only considered dynamic scheduling, and generally had exponential complexity. However, for many embedded systems running on limited resources, preemptive scheduling may be very costly due to high context switching and memory overheads, and dynamic scheduling can be less desirable due to high CPU overhead. In this paper, we study static priority scheduling of recurring real-time tasks. We focus on and obtain schedule-theoretic results for the non-preemptive uniprocessor case. To achieve this, we derive a sufficient (albeit not necessary) condition for schedulability under static priority scheduling and show that this condition can be efficiently tested in practice. The latter technique is demonstrated with examples, where in each case, an optimal solution for a given problem specification is obtained within reasonable time, by first detecting good candidates using meta-heuristics, and then by testing them for schedulability.

A decision support system for locating VHF/UHF radio jammer systems on the terrain

In this study, a mathematical model is suggested concerning the location of VHF/UHF frequency radio jammer systems to the terrain parts to conduct single frequency or sequential frequency jamming, and then a decision support system (DSS), based on the suggested model, is formed. Location problem is modelled by the maximum covering location problem and LINGO-8 package program is used to solve the model. Interaction with the user is provided via the MS-Excel program in the DSS. In the application part of the study, a scenario was set up and the model was run for the two cases, weighted and equally weighted situations of the targets. With the same scenario, backup positions for the jammer systems were tried to be determined and solutions for the scenario were evaluated.

Method of characteristic functions for classes of networks with fixed node degrees

Classes of networks with fixed node degrees and weights (capacities) of arcs and loops not exceeding a given parameter are studied. Characteristic functions are found that depend on vector components and a parameter; the nonnegativeness of this parameter is the network existence criterion, the degrees of its nodes are equal to vector components, and the arc weights do not exceed the parameter. The set of nodes of such networks are decomposed into two subsets. The sums of arc weights on each subset and the sum of arc weights incident upon the nodes of both subsets are considered as variables. Formulas for the upper and lower bounds for these variables are obtained. The results can be used for the calculation of flows in networks because since node partitioning determines the network cut.     

Enable delegation for RBAC with Secure Authorization Certificate

Our motivation in this paper is to explore a Secure Delegation Scheme that could keep access control information hidden through network transmission. This approach introduces the quasirandom structure, 3-Uniform Hypergraph, as the representation structure for authorization information. It generates a Secure Authorization Certificate (SAC) in place of an Attribute Certificate (AC) to enable both Role-based Access Control (RBAC) and a delegation process for hiding authorization information. We have two contributions in this regard: (1) a value-based delegation scheme and (2) a pattern-based RBAC. A Secure Delegation Scheme is based on the hashing values generated with the quasirandom structure. With this scheme, the delegation process will greatly reduce the risk of sensitive authorization information leakage for applications. In the case of pattern-based access, we introduce a new hash function using quasirandom structure to make a fingerprint¹ for RBAC. The quasirandom structure derived from k-Uniform Hypergraph has measurable uniformity, which is an advantage over traditional hash functions. Another advantage is that it does not need to access the entire message context to generate the fingerprint which is essential for traditional hash functions such as MD5, SHA-1, etc.     

Evaluation of perceived and self-reported manual forces exerted in occupational materials handling

The main objective of the study was to evaluate the ability of workers to reproduce simulated manual work forces correctly and to quantify these forces in Newtons (N) by means of self-reports. Fourteen male and 14 female workers participated in the study. Three experiments were carried out. In the first experiment, the ability to reproduce the magnitudes of simulated manual forces occurring in daily work and to estimate these forces in Newtons was tested. A specially designed force-measuring device was used for this purpose. In the second experiment, the subjects estimated the weights of five boxes ranging from 1 to 30 kg. In the third experiment, the subjects were asked to produce five predetermined push and pull forces ranging in magnitude from 10 to 300 N on to the handle of the force-measuring device. The ability to reproduce the magnitudes of manual forces when simulating four familiar work tasks was good (the intraclass correlation coefficients ranged from 0.75 to 0.95). The ability to quantify these forces in Newtons was not as good (the product moment correlation coefficients ranged from 0.21 to 0.69). When the subjects estimated the weights of boxes they underestimated the weights. When they produced predetermined push and pull forces they exerted higher forces than expected when low force levels were requested and lower forces when high force levels were requested. However, the forces were correctly ranked. In summary, simulation of the manual push/pull forces used in familiar work tasks seemed to offer sufficient reproducibility to be worth testing for validity. Self-reports, used without previous training or without known 'reference forces', seemed to be very rough when the aim was to estimate in kg or Newtons. However, the fact that individuals could rank the forces correctly opens a potential for refinement of self-reports as a method for quantifying manual forces in objective terms, e.g. kg or Newtons.     

An interactive sorting method for additive utility functions

In this paper, we consider the problem of placing alternatives that are defined by multiple criteria into preference-ordered categories. We consider a method that estimates an additive utility function and demonstrate that it may misclassify many alternatives even when substantial preference information is obtained from the decision maker (DM) to estimate the function. To resolve this difficulty, we develop an interactive approach. Our approach occasionally requires the DM to place some reference alternatives into categories during the solution process and uses this information to categorize other alternatives. The approach guarantees to place all alternatives correctly for a DM whose preferences are consistent with any additive utility function. We demonstrate that the approach works well using data derived from ranking global MBA programs as well as on several randomly generated problems.     

Block copolymers of cyclohexene oxide and ketonic resins via condensation and promoted cationic polymerization

Block copolymers of cyclohexene oxide (CHO) and ketonic resin were prepared by using ketonic resins as free radical photoinitiators via two‐step procedure. In the first step, cyclohexanone–formaldehyde and acetophenone–formaldehyde resins were modified during their preparation with benzoin and benzoin isobutyl ether. Then, AB or ABA type block copolymers depending on the resin employed were obtained by irradiation of these resins in the presence of pyridinium salt and CHO as a cationically polymerizable monomer. By this way, block copolymers of CHO with ketonic resin were prepared and characterized by GPC, DCS, FTIR, and ¹H NMR spectral measurements. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007