Observations on the blood supply of the epidymis in the rat and man

It is clear that the functions of the mammalian epididymis are still worthy of further investigation. There can be no difficulty in accepting the epididymal role in sperm transport, sperm storage, and in sperm preservation, but the more precise properties of the epididymal secretions and their physiological relationship to the life cycle of the spermatozoon are still matters for conjecture. The regularity with which tuberculous lesions settle in the tail of the epididymis and the rapidity with which corc -1 infections spread to involve the testis are problems of more than ordinary interest to the clinician and the pathologist. Furthermore the effects of epididymal obstructions, both high and low, are of fundamental importance to all students of fertility and sterility.The anatomy of the blood supply of the testis in Man and various species of mammals has recently been re- investigated (Harrison & Barclay, 1948; Harrison, 1949) and the effects of both temporary and permanent occlusion of the testicular artery studied in the rat (Oett14 & Harrison, 1952). It is clear from the work of these authors that the complicated vascular pattern of the testicular artery is of functional importance, has various clinical implications and may be part of a thereto- regulatory mechanism. It was in the hope that an examination of the blood supply of the epididymis in the rat and in Man might provide additional information on its functions in health and disease, that this investigation was undertaken

The concept of regeneration in Christian thought

Who is the Christian? What does it mean to be a "new man" in Christ? What does it mean to be "born again"? Is this the same as the Pentecostal expression "the baptism in the Holy Spirit"? And what are we to make of the phrase, "the baptism in/with the Holy Spirit"? What is the relationship between water baptism and spirit baptism? What is the relation of regeneration to baptism? Does baptism alone constitute the complete rite of initiation, or is something more required? How is a person's initiation into the Christian way to be described and understood? What is Christian baptism? What is its place in the plan of salvation? When is the Holy Spirit given?In search of an authentic theology of the Christian, we have treated the writings of the Fourth Evangelist, Cyril of Jerusalem and Ambrose of Milan, John Calvin, Karl Barth and modern day Pentecostalists and NeoPentecostalists.The work, although not divided into specific parts, has two aspects. First of all, there is a full exposition of how the term, regeneration, has been treated in each of the above theologies. From this it can be seen that various interpretations of the concept have emerged in the church over the centuries.The second aspect is an examination of four critical categories surrounding our theme, namely, regeneration, initiation, water baptism and spirit baptism. Today is an opportune time to understand the various inter¬ relationships of these categories, both from the point of view of the pastoral ministry of the churches and the life of the individual Christian.In the course of our study, various other topics are touched upon: the nature of faith, the relation of baptism to confirmation, the paedobaptist debate, the need to restore a Spirit Christology either alongside, or instead of, Logos Christology, the nature of the gift of speaking in tongues and its place in the fellowship of the church. Each of these subjects requires a thesis of its own, and we have by no means exhausted their significance, although they have necessitated comment because of their relationship to our central theme

Geomagnetic jerks during the Swarm era and impact on IGRF-12

Global geomagnetic field models can be used to study the dynamics of the core, aid satellite operation and make global digital navigation possible – from smartphones to guided drilling. While current models capture the long-period and large-scale features and variations of the core field well, it is often difficult to represent the poorly understood small-scale and rapid behaviour of the field, thus making prediction difficult. The mantle and crust filter small-scale spatial and temporal features originating in the Earth’s core, and field sources external to the Earth contaminate the observations we have. Geomagnetic jerks represent the most rapid observed variations of the internal field, on the scale of months to years. We investigate the occurrence and spatiotemporal characteristics of jerks in ground observatory data and a recent global field model, during the Swarm era. Previous reports suggest that global models show regions of high secular acceleration associated with the 2014 jerk and that expressions of this might be seen at European observatories post-2014. We find limited evidence of a jerk in European observatories around 2014, but do find globally widespread evidence, and our models of this signal are in agreement with independent field models. We also find evidence of a new jerk, after the 2014 event, in observatory data. In response to these events we show the impact on early, and potential future, discrepancies between International Geomagnetic Reference Field (IGRF) predictions and observations in the period of 2015-2020 as a result of the unpredictable, non-linear secular variation of jerks now known to have occurred. With the 2014 jerk occurring during / immediately after the data collection period for IGRF-12 and a subsequent jerk occurring shortly after release, we highlight the deviation from observations, the comparable performance of both simple and complex predictive models and the importance of utilising the ability to regularly update field models. This is likely to remain the case until the rapid dynamics of the core are better understood

Statistical forecasting techniques applied to observatory data for core field modelling

Modelling of the geomagnetic field is a complex challenge, hindered by noisy and incomplete ground and satellite observations, and the extent to which we can separate the contributions of the various field sources in these data. Forecasting of the core field and its time variations (secular variation), an activity of key interest for academic and applied studies of geomagnetism and space weather, is further complicated by an incomplete knowledge of the physics controlling magnetic field generation. Predictive core field models often rely on simple mathematical extrapolation to produce short term (<5 year) forecasts, but this technique can struggle when rapid variations known as geomagnetic jerks cause distinctly non-linear secular variation to occur. More advanced physics-based forecasting techniques such as core flow advection and geodynamo data assimilation also currently struggle to capture such short timescale variations. We discuss the applicability of common statistical forecasting techniques to ground observatory time series and compare the results of models based on such data forecasts to those of simple field model extrapolation and core flow advection forecasts

Analysis of Errors in Simple Geomagnetic Field Model Predictions

The secular variation and secular acceleration of the Earth’s geomagnetic core field pose a difficult challenge for field modellers, and particularly for forecasting future evolution of the field. Models must describe the scope of spatial and temporal changes, which are often poorly resolved and masked by variations of other field sources, and parameterise the observed signals accordingly. In retrospect, variations can be accurately modelled using observations from the global network of ground observatories and satellites, but for practical applications, field models are used to predict the future state of the field. Models such as the International Geomagnetic Reference Field and World Magnetic Model are produced on a quinquennial basis, and predict the core field for the subsequent 5 years. These models are widely used in academia, industry and by governmental and international organisations for purposes such as navigation, mineral exploration and space physics. Given our incomplete understanding of the physical state of the outer core however, such predictive models are often based on simple extrapolations. We quantify the error from regular extrapolations in a range of core field models, in order to negate the effects of data availability and those arising near model ends. We investigate the presence and predictability of temporal and spatial trends in these errors. Our tests confirm the impact of jerks and high latitude effects, and also suggest predictions are less reliable over the South Atlantic Anomaly. We note that global prediction errors are correlated with external field sources temporally

Geomagnetic jerks in the Swarm Era

The timely provision of geomagnetic observations as part of the ESA Swarm mission means analysis and modelling can be conducted rapidly and kept up-to-date in a manner not possible before. Observations from each of the three satellites in the Swarm constellation at 1Hz are available within 4 days and hourly mean ground observatory network measurements (AUX_OBS_2) are updated every 3 months by the British Geological Survey (BGS). This makes it possible to study very recent changes of the magnetic field. In particular here we investigate variations known as geomagnetic jerks. Given that jerks represent (currently) unpredictable changes in the internal geomagnetic field, we ask what impact they might have on the accuracy of the International Geomagnetic Reference Field Model (IGRF). The 12th generation of the IGRF was last updated using observations up to mid-2014 and provides a snapshot of the geomagnetic field at 2015 as well as a prediction of variations until 2020

How “Point Blindness” Dilutes the Value of Stock Market Reports

The stock index “point” is a focal component of financial news reports. While much attention is paid to changes in stock index point totals, few people realize that the value of a stock index “point” varies (and has recently declined). We call this perceptual phenomenon “point blindness” and explain its threat to investors. Simple changes in media presentations of stock index information can counter point blindness. These changes are easy to implement and can help audiences make better financial decisions. An experiment on over 2000 participants shows such changes significantly altering their perceptions of the stock market.personal finance; money illusion; behavioral finance; behavioral economics; communication; currencies