On the Integration of Smalltalk and Java

After decades of development in programming languages and programming environments, Smalltalk is still one of few environments that provide advanced features and is still widely used in the industry. However, as Java became prevalent, the ability to call Java code from Smalltalk and vice versa becomes important. Traditional approaches to integrate the Java and Smalltalk languages are through low-level communication between separate Java and Smalltalk virtual machines. We are not aware of any attempt to execute and integrate the Java language directly in the Smalltalk environment. A direct integration allows for very tight and almost seamless integration of the languages and their objects within a single environment. Yet integration and language interoperability impose challenging issues related to method naming conventions, method overloading, exception handling and thread-locking mechanisms. In this paper we describe ways to overcome these challenges and to integrate Java into the Smalltalk environment. Using techniques described in this paper, the programmer can call Java code from Smalltalk using standard Smalltalk idioms while the semantics of each language remains preserved. We present STX:LIBJAVA - an implementation of Java virtual machine within Smalltalk/X - as a validation of our approach

Bilateral impairment of concurrent saccade programming in hemispatial neglect

When healthy observers make a saccade that is erroneously directed toward a distracter stimulus, they often produce a corrective saccade within 100ms after the end of the primary saccade. Such short inter-saccadic intervals indicate that programming of the secondary saccade has been initiated prior to the execution of the primary saccade and hence that the two saccades have been programmed concurrently. Here we show that concurrent saccade programming is bilaterally impaired in left spatial neglect, a strongly lateralized disorder of visual attention resulting from extensive right cerebral damage. Neglect patients were asked to make saccades to targets presented left or right of fixation while disregarding a distracter presented in the opposite hemifield. We examined those experimental trials on which participants first made a saccade to the distracter, followed by a secondary (corrective) saccade to the target. Compared to healthy and right-hemisphere damaged control participants the proportion of secondary saccades directing gaze to the target instead of bringing it even closer to the distracter was bilaterally reduced in neglect patients. In addition, the characteristic reduction of secondary saccade latency observed in both control groups was absent in neglect patients, whether the secondary saccade was directed to the left or right hemifield. This pattern is consistent with a severe, bilateral impairment of concurrent saccade programming in left spatial neglect.

Reduced endurance of the cervical flexor muscles in patients with concurrent temporomandibular disorders and neck disability

Subjects with temporomandibular disorders (TMDs) have been found to have clinical signs and symptoms of cervical dysfunction. Although many studies have investigated the relationship between the cervical spine and TMD, no study has evaluated the endurance capacity of the cervical muscles in patients with TMD. Thus the objective of this study was to determine whether patients with TMD had a reduced endurance of the cervical flexor muscles at any level of muscular contraction when compared with healthy subjects. One hundred and forty-nine participants provided data for this study (49 subjects were healthy, 54 had myogenous TMD, and 46 had mixed TMD). There was a significant difference in holding time at 25% MVC between subjects with mixed TMD when compared to subjects with myogenous TMD and healthy subjects. This implies that subjects with mixed TMD had less endurance capacity at a lower level of contraction (25% MVC) than healthy subjects and subjects with myogenous TMD. No significant associations between neck disability, jaw disability, clinical variables and neck flexor endurance test were found.

A Morphological Box for Handling Temporal Data in B2C Systems

User interfaces are key properties of Business-to-Consumer (B2C) systems, and Web-based reservation systems are an important class of B2C systems. In this paper we show that these systems use a surprisingly broad spectrum of different approaches to handling temporal data in their Web inter faces. Based on these observations and on a literature analysis we develop a Morphological Box to present the main options for handling temporal data and give examples. The results indicate that the present state of developing and maintaining B2C systems has not been much influenced by modern Web Engi neering concepts and that there is considerable potential for improvement.

Remodeling of calcium handling in skeletal muscle through PGC-1?: impact on force, fatigability, and fiber type

Regular endurance exercise remodels skeletal muscle, largely through the peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). PGC-1α promotes fiber type switching and resistance to fatigue. Intracellular calcium levels might play a role in both adaptive phenomena, yet a role for PGC-1α in the adaptation of calcium handling in skeletal muscle remains unknown. Using mice with transgenic overexpression of PGC-1α, we now investigated the effect of PGC-1α on calcium handling in skeletal muscle. We demonstrate that PGC-1α induces a quantitative reduction in calcium release from the sarcoplasmic reticulum by diminishing the expression of calcium-releasing molecules. Concomitantly, maximal muscle force is reduced in vivo and ex vivo. In addition, PGC-1α overexpression delays calcium clearance from the myoplasm by interfering with multiple mechanisms involved in calcium removal, leading to higher myoplasmic calcium levels following contraction. During prolonged muscle activity, the delayed calcium clearance might facilitate force production in mice overexpressing PGC-1α. Our results reveal a novel role of PGC-1α in altering the contractile properties of skeletal muscle by modulating calcium handling. Importantly, our findings indicate PGC-1α to be both down- as well as upstream of calcium signaling in this tissue. Overall, our findings suggest that in the adaptation to chronic exercise, PGC-1α reduces maximal force, increases resistance to fatigue, and drives fiber type switching partly through remodeling of calcium transients, in addition to promoting slow-type myofibrillar protein expression and adequate energy supply.

Concurrent and predictive validation of a novel robotic surgery simulator: a prospective, randomized study

We evaluated the concurrent and predictive validity of a novel robotic surgery simulator in a prospective, randomized study.

The influence of handling and exposure to a ferret on body temperature and running wheel activity of golden hamsters (Mesocricetus auratus)

In order to determine a stress response, two groups of twenty male golden hamsters were either exposed to a ferret or handled by a human. The hamsters' body temperature and running wheel activity were measured as stress correlates. Half of the hamsters' cages were equipped with a functional running wheel to determine whether the presence of a running wheel might reduce stress. Exposure to the ferret was followed by a significant increase in body temperature and running wheel revolutions: however, running wheel activity did not change after handling. Body temperature increased less after handling in hamsters living in a cage with a functional running wheel than in those with a non-revolving running wheel. This suggests that hamsters with a functional running wheel reacted less strongly to acute stress caused by handling. On the other hand, temperature increase after the exposure to a ferret was not affected by the presence of a running wheel. Both exposure to a ferret and handling caused stress in golden hamsters, as demonstrated by an increase in body temperature (emotional fever). Stress caused by handling was much milder than stress caused by the ferret. (C) 2011 Elsevier B.V. All rights reserved.

Cardiac G-protein-coupled receptor kinase 2 ablation induces a novel Ca2+ handling phenotype resistant to adverse alterations and remodeling after myocardial infarction

G-protein-coupled receptor kinase 2 (GRK2) is a primary regulator of β-adrenergic signaling in the heart. G-protein-coupled receptor kinase 2 ablation impedes heart failure development, but elucidation of the cellular mechanisms has not been achieved, and such elucidation is the aim of this study.