’n Besinning oor die aard van die fisiese werklikheid

Reflections on the nature of physical reality According to T.S. Kuhn the history of a particular field of science is characterised by successive phases of problem solving, and each phase of problem solving is paradigmatically founded. A paradigm, like a worldview, expresses the deepest meaning and significance of reality. Man’s rational mind is, however, too limited in capacity to describe the complexity of reality in a scientific way. In an attempt to describe reality, reality thus has to be simplified. For instance, in order to present a description of the formation of the universe evolving from the big bang to a functional and efficient structure, the functionality as well as the structure of the universe with its billions of stars and star systems has to be simplified dramatically by an imaginative model. Such a simplified model is described by the big bang theory. Science brings to the fore questions regarding the deeper meaning and significance of reality, for instance the anthropic principle, on which only the Word of God can offer a perspective. All our observations are restrained by actualities such as finite velocity of light and our human boundness to time. Consequently, theories of evolution with an elementary beginning cannot be verified as valid and are therefore questionable. The same applies to verifying the process of evolution before man’s existence on earth. Furthermore, man can obtain no knowledge of the nature of time during God’s supernatural acts of creation as revealed by the Word of God. Nevertheless, it appears that even an idealistic theory of evolution that cannot be verified empirically can provide man with revelatory elements of God’s works, wisdom and omnipotence

Skepping en evolusie ’n filosofiese besinning oor tyd, ruimte en materie

This philosophical reflection on time, space and matter in the debate creationevolution accepts that the universe came into existence as a number of acts of deliberate supernatural creation by an already existing God. Since the first human couple was created on the sixth day, the creation evolves in all spheres of life with time passing by. Accepting time linearity and physical uniformitarianism, disregarding supernatural acts and catastrophes, natural sciences reconstruct the past from the present. The result is ages of thousands of million years for the earth and early life, and for a universe, having a size in terms of this number of light-years. None of these assumptions and results can be verified. Physical evolution requires theoretical explanations beyond the very limited observational data at our disposal and cannot be considered as revealed truth. Furthermore, naturalism is inherent in modern science and cannot explain the full richness of our experienced reality

Unenhanced CT imaging is highly sensitive to exclude pheochromocytoma: A multicenter study

Background: A substantial proportion of all pheochromocytomas is currently detected during the evaluation of an adrenal incidentaloma. Recently, it has been suggested that biochemical testing to rule out pheochromocytoma is unnecessary in case of an adrenal incidentaloma with an unenhanced attenuation value ≤10Hounsfield Units (HU) at computed tomography (CT). Objectives: We aimed to determine the sensitivity of the 10HU threshold value to exclude a pheochromocytoma. Methods: Retrospective multicenter study with systematic reassessment of preoperative unenhanced CT scans performed in patients in whom a histopathologically proven pheochromocytoma had been diagnosed. Unenhanced attenuation values were determined independently by two experienced radiologists. Sensitivity of the 10HU threshold was calculated, and interobserver consistency was assessed using the intraclass correlation coefficient (ICC). Results: 214 patients were identified harboring a total number of 222 pheochromocytomas. Maximum tumor diameter was 51 (39–74)mm. The mean attenuation value within the region of interest was 36±10HU. Only one pheochromocytoma demonstrated an attenuation value ≤10HU, resulting in a sensitivity of 99.6% (95% CI: 97.5–99.9). ICC was 0.81 (95% CI: 0.75–0.86) with a standard error of measurement of 7.3HU between observers. Conclusion: The likelihood of a pheochromocytoma with an unenhanced attenuation value ≤10HU on CT is very low. The interobserver consistency in attenuation measurement is excellent. Our study supports the recommendation that in patients with an adrenal incidentaloma biochemical testing for ruling out pheochromocytoma is only indicated in adrenal tumors with an unenhanced attenuation value >10HU

Natuurwetenskaplike kennis en die Woord van God

Natural science knowledge and the Word of God The Greek philosophers denied that true knowledge could be obtained by observing the sensory world. True knowledge rela- ted only to things that were unchanging, immutable. For Pytha- goras and Plato that meant, first of all, mathematics. Following the Pythagorean-Platonian tradition, many early scientists held that mathematical order represented the most real and certain aspect of the world. Galileo moved science away from ordinary observations toward mathematical reasoning. For Galileo the abstract, idealistic world was the real world. However, in the natural world, which is anarchic and far from equilibrium, energy transfer represents a source of order, creativity and growth. Al- so, new assemblages of species appeared after large numbers of species had gone extinct in earth’s history. These surges of energy transfer cannot be described by linear time. Scripture does not reveal to us the workings of nature – we can only learn about it through scientific methods. However, those who do not acknowledge God’s supernatural acts of creation are forced to search for other answers through their own thinking about the origin, purpose, meaning and interrelatedness of everything. It is shown that the successive acts of creation in Genesis 1 are reconcilable with current knowledge of the natural sciences

Vrugbare wetenskappe

At creation God gave man the task to subdue the earth and to keep it. Every beast and every bird was brought to man to give an appropriate name to each of them. Therefore, man had to observe them and analyze his observations scientifically. Science of today was founded by the Greek philosophers from 600 BC, making science again part of man's task. In particular Aristotle’s science was fruitful, with an impact over a period of about 2000 years. More recently, the science of Newton led to a mathematically description of experimental observations and a penetrating control of nature by precise instruments. A few centuries later Einstein's theory of relativity showed its fruitfulness in the description and explanation of observations in the universe. Darwin’s evolutionary naturalism introduced a historic approach to synthesize observations; experimental observations became less important. According to evolutionary naturalism, all higher order living entities, including man, came forth by chance throughnatural forces (resembling mysticism?), dehumanizing man to a product of nature.http://reference.sabinet.co.za.nwulib.nwu.ac.za/webx/access/electronic_journals/tcwet/tcwet_v49_n4_a3.pd

Long-term neutron monitor observations and the 2009 cosmic ray maximum

The solar minimum of 2009 was characterized by a prolonged increase toward the maximum cosmic ray intensity, which was higher than it was during the maxima of 22 and 44 years ago. In the previous two so-called qA <0 (solar dipole moment facing South) magnetic cycles, these increases were more sharply peaked than in 2009. The observations of the Sanae, Hermanus, Potchefstroom, and Tsumeb neutron monitors are used to investigate this behavior in terms of propagation conditions due to solar activity, the heliospheric magnetic field, and the profile of the wavy current sheet in the field. This 2009 cosmic ray maximum can only be understood after an investigation of the long-term cosmic ray record. This study is augmented by observations of eight other neutron monitors. During 2009, solar activity parameters were significantly different from previous solar minima: The sun was much quieter, and the the heliospheric magnetic field was more than 20% weaker than during other recent minima. Both of these parameters imply a higher cosmic ray diffusion coefficient, which provides a natural explanation for both the higher galactic cosmic ray intensities that were observed and the absence of such an effect for anomalous cosmic ray

Investigation of the multiple-component structure of the 20 January 2005 cosmic ray ground level enhancement

Worldwide observations of the cosmic ray ground level enhancement (GLE) of 20 January 2005 are used to investigate a commonly observed but poorly understood feature of this class of event. It is argued that the GLE comprised two distinctly different cosmic ray populations. The first resulted in an impulsive, highly anisotropic, field-aligned pulse with a relatively hard rigidity spectrum and significant velocity dispersion. The characteristics of the anisotropy were almost identical to those for similar impulsive increases observed during GLEs in 1960, 1978, and 1989. The p 0 g ray observations from the RHESSI and CORONAS-F spacecraft and Type III radio emissions yield a path length of 1.76 ± 0.1 AU to Earth for the first pulse. After the highest energies in the initial anisotropic pulse had passed Earth, another field-aligned but mildly anisotropic cosmic ray pulse developed slowly worldwide, exhibiting the characteristics of the conventional GLE. The risetime and anisotropy of this second population indicate substantial scattering, apparently at variance to the essentially scatter-free nature of the initial pulse. We show that the coexisting scatter-free initial impulsive increase and the diffusive character of the second pulse are consistent with the standard quasi-linear theory of pitch angle diffusion. Throughout the GLE, the anisotropy remained field-aligned, and a third maximum, seen by some stations, is shown to be due to changes in the direction of the heliospheric magnetic field (HMF). Examination of 22 large (>20%) GLEs in the historical record shows that the impulsive pulse never occurs after the commencement of the P2 pulse, indicating that the impulsive-gradual combination is not due to a chance sampling of differing scattering regions of the HMF. It is further shown that impulsive pulses, or their equivalents, have been observed in 13 out of the 15 GLEs associated with solar activity in the solar longitude range 24° –98°W, leading us to propose that the event of 20 January 2005 should be regarded as the defining example of the GLE. The observations lead us to propose two separate acceleration episodes in the typical GLE: (1) acceleration directly associated with the flare itself and located in the lower corona and (2) acceleration by a supercritical shock driven by the associated coronal mass ejection, located at 3–5 solar radii and farther in the upper corona. A one-to-one association with so-called impulsive and gradual solar energetic particle events at lower energies is proposed. On the basis of these observations, a generic model for the GLE is propose