Comparative Analysis of the Visual, Refractive and Aberrometric Outcome with the Use of 2 Intraocular Refractive Segment Multifocal Lenses

To demonstrate the results of ray tracing higher- and lower-order aberrations in pseudophakic eyes with rotationally asymmetrical segment multifocal lenses, total high- and low-order aberrations, measured by root mean square value (RMS), refraction, uncorrected distance and uncorrected near visual acuity (UCDVA and UCNVA), and tear break-up time, were measured at scotopic size in 42 eyes of patients implanted with bifocal refractive Mplus15/Mplus30 IOL with +1.5 dpt near addition (42 eyes of patients implanted with Mplus15)/+3.0 dpt near addition (91 eyes of patients implanted with Mplus30), and 107 eyes of control group. No significant differences were noticed between the examined groups concerning UCDVA, UCNVA, and tear break-up time (p < 0.001). Coma and total high-order aberrations were significantly higher for the Mplus30 lens in comparison to the Mplus15 lens and the control group (Coma, Trefoil p < 0.001, Secondary Astigmatism p = 0.002). The spherical aberrations were significantly higher in the lower-addition lens (p = 0.016) in comparison to the control group and to the higher-addition lens group (p < 0.001). Both intraocular lens models were successful at reaching refractive aim, good distance, and near function with the lower higher-order aberrations for the low-addition lens

Elevated Colon Cancer Rates Linked to Prior Appendicitis: A Retrospective Cohort Study Based on Data from German General Practices

Background/Objective: The association between appendicitis and colon cancer is not yet fully understood. Previous studies have shown contradictory results. Currently, no population-based data from Germany are available with regard to the incidence of colon cancer following appendicitis. This study investigated the association between appendicitis and the incidence of colon cancer in Germany. Methods: In this retrospective cohort study, the incidence of colon cancer was compared for patients with appendicitis and patients without appendicitis, matched for age, sex, index year, average annual consultation frequency, and comorbidity. The aim of the study was to explore the relationship between appendicitis and the incidence of colon cancer. The evaluation was carried out using logistic regression analyses. Results: The study included 49,790 people with and without appendicitis, with a median age of 41 years. During a follow-up period of up to 15 years, 1.04% of cases with appendicitis and 0.60% of cases without appendicitis were newly diagnosed with colon cancer, with some 36.4% of colon cancer cases diagnosed within the first six months after appendicitis. Regression analyses revealed a significant association between appendicitis and colon cancer, particularly in men and in the age groups 41–50 (HR: 10.30; 95% CI: 1.03–43.82) and 18–30 years (HR: 8.17; 95% CI: 1.03–64.58). Conclusions: The present retrospective cohort study suggests an association between appendicitis and the incidence of colon cancer in Germany. Based on our results, we recommend offering a colonoscopy or at least a stool test within 12 months after appendicitis, especially for 18–50-year-olds and >60-year-olds in good general health

TRPC3 Is Downregulated in Primary Hyperparathyroidism

Transient receptor potential canonical sub-family channel 3 (TRPC3) is considered to play a critical role in calcium homeostasis. However, there are no established findings in this respect with regard to TRPC6. Although the parathyroid gland is a crucial organ in calcium household regulation, little is known about the protein distribution of TRPC channels—especially TRPC3 and TRPC6—in this organ. Our aim was therefore to investigate the protein expression profile of TRPC3 and TRPC6 in healthy and diseased human parathyroid glands. Surgery samples from patients with healthy parathyroid glands and from patients suffering from primary hyperparathyroidism (pHPT) were investigated by immunohistochemistry using knockout-validated antibodies against TRPC3 and TRPC6. A software-based analysis similar to an H-score was performed. For the first time, to our knowledge, TRPC3 and TRPC6 protein expression is described here in the parathyroid glands. It is found in both chief and oxyphilic cells. Furthermore, the TRPC3 staining score in diseased tissue (pHPT) was statistically significantly lower than that in healthy tissue. In conclusion, TRPC3 and TRPC6 proteins are expressed in the human parathyroid gland. Furthermore, there is strong evidence indicating that TRPC3 plays a role in pHPT and subsequently in parathyroid hormone secretion regulation. These findings ultimately require further research in order to not only confirm our results but also to further investigate the relevance of these channels and, in particular, that of TRPC3 in the aforementioned physiological functions and pathophysiological conditions

Diagnosis, Treatment and Long-Term Management of Vitamin B12 Deficiency in Adults: A Delphi Expert Consensus

Background/Objectives: Vitamin B12 deficiency can cause variable symptoms, which may be irreversible if not diagnosed and treated in a timely manner. We aimed to develop a widely accepted expert consensus to guide the practice of diagnosing and treating B12 deficiency. Methods: We conducted a scoping review of the literature published in PubMed since January 2003. Data were used to design a two-round Delphi survey to study the level of consensus among 42 experts. Results: The panelists agreed on the need for educational and organizational changes in the current medical practices for diagnosing and treating B12 deficiency. Recognition of clinical symptoms should receive the highest priority in establishing the diagnosis. There is agreement that the serum B12 concentration is useful as a screening marker and methylmalonic acid or homocysteine can support the diagnosis. Patient lifestyle, disease history, and medications can provide clues to the cause of B12 deficiency. Regardless of the cause of the deficiency, initial treatment with parenteral B12 was regarded as the first choice for patients with acute and severe manifestations of B12 deficiency. The use of highdose oral B12 at different frequencies may be considered for long-term treatment. Prophylactic B12 supplementation should be considered for specific high-risk groups. Conclusions: There is a consensus that clinical symptoms need to receive more attention in establishing the diagnosis of B12 deficiency. B12 laboratory markers can support the diagnosis. The severity of clinical symptoms, the causes of B12 deficiency, and the treatment goals govern decisions regarding the route and dose of B12 therapy

Phosphopeptide binding to the N-SH2 domain of tyrosine phosphatase SHP2 correlates with the unzipping of its central β-sheet

SHP2 is a tyrosine phosphatase that plays a regulatory role in multiple intracellular signaling cascades and is known to be oncogenic in certain contexts. In the absence of effectors, SHP2 adopts an autoinhibited conformation with its N-SH2 domain blocking the active site. Given the key role of N-SH2 in regulating SHP2, this domain has been extensively studied, often by X-ray crystallography. Using a combination of structural analyses and molecular dynamics (MD) simulations we show that the crystallographic environment can significantly influence the structure of the isolated N-SH2 domain, resulting in misleading interpretations. As an orthogonal method to X-ray crystallography, we use a combination of NMR spectroscopy and MD simulations to accurately determine the conformation of apo N-SH2 in solution. In contrast to earlier reports based on crystallographic data, our results indicate that apo N-SH2 in solution primarily adopts a conformation with a fully zipped central β-sheet, and that partial unzipping of this β-sheet is promoted by binding of either phosphopeptides or even phosphate/sulfate ions

Postmortem sympathomimetic iris excitability

Background:: A reliable estimation of time since death can be important for the law enforcement authorities. The compound method encompassing supravital reactions such as the chemical excitability of the iris can be used to further narrow intervals estimated by temperature-based methods. Postmortem iris excitability was mostly assessed by parasympatholytic or parasympathomimetic substances. Little is known regarding sympathomimetic agents. The present study aims to describe the postmortem iris excitability using the sympathomimetic drug phenylephrine. Methods:: Cadavers were included after body donors gave written informed consent during lifetime. Exclusion criteria were known eye disease, or a postmortem interval exceeding 26 hours. A pupillometer with a minimum measurement range of 0.5 mm was used to determine the horizontal pupil diameter before and 20 minutes after the application of phenylephrine. Increase in pupil diameter was labeled as positive reaction, unchanged pupil diameter was labeled as negative reaction, and decrease in pupil diameter was labeled as paradox reaction. Results:: 30 eyes from 16 cadavers (median age = 80.0; 9 males, 7 females) were examined. Initial pupil size was in median 3.5 mm (interquartile range [IQR]: 3.0–4.5 mm) and progressed to 4.0 mm (IQR: 3.5–5.0 mm) 20 minutes after drug instillation. The achieved pupil diameter difference comprised in median 0.5 mm (IQR: 0.0–1.0 mm). A positive reaction was observed in 21 cases. Negative reactions were observed in 5 cases and paradox reactions in 4 cases. Overall, there was a statistically significant difference in diameter between the initial and the reactive pupil (P = 0.0002). Conclusion:: Although relatively rarely used, sympathomimetic drugs seem to be eligible for chemical postmortem iris excitability. Currently, assessment of postmortem iris excitability usually only involves parasympatholytic and parasympathomimetic agents. The findings of the present study give a hint that the application of a third agent with a sympathomimetic mechanism of action could provide additional information. Further studies assessing such a triple approach in the compound method in comparison with the current gold standard for estimation of time since death are mandatory to ensure reliable results

PIEZO1-mediated mechanosensing governs NK-cell killing efficiency and infiltration in three-dimensional matrices

Natural killer (NK) cells play a vital role in eliminating tumorigenic cells. Efficient locating and killing of target cells in complex three-dimensional (3D) environments are critical for their functions under physiological conditions. However, the role of mechanosensing in regulating NK-cell killing efficiency in physiologically relevant scenarios is poorly understood. Here, we report that the responsiveness of NK cells is regulated by tumor cell stiffness. NK-cell killing efficiency in 3D is impaired against softened tumor cells, whereas it is enhanced against stiffened tumor cells. Notably, the durations required for NK-cell killing and detachment are significantly shortened for stiffened tumor cells. Furthermore, we have identified PIEZO1 as the predominantly expressed mechanosensitive ion channel among the examined candidates in NK cells. Perturbation of PIEZO1 abolishes stiffness-dependent NK-cell responsiveness, significantly impairs the killing efficiency of NK cells in 3D, and substantially reduces NK-cell infiltration into 3D collagen matrices. Conversely, PIEZO1 activation enhances NK killing efficiency as well as infiltration. In conclusion, our findings demonstrate that PIEZO1-mediated mechanosensing is crucial for NK killing functions, highlighting the role of mechanosensing in NK-cell killing efficiency under 3D physiological conditions and the influence of environmental physical cues on NK-cell functions

Die Rolle von TRPC-Kanälen in Astrozyten des Rückenmarks

Die vorliegende Arbeit beschäftigt sich mit der Charakterisierung von Transient Rezeptor Potential (TRP)-Ionenkanälen in primären Astrozyten aus dem Rückenmark der Maus mit Hilfe von immunzytochemischen Färbungen, Migrations- und Proliferationsassays, sowie fluorometrische Messungen der cytosolischen Ca2+-Konzentration (Calcium-Imaging). Die zahlenmäßig am stärksten vertretenen Zellpopulationen in Rückenmarkskulturen aus der Maus stellen Astrozyten, Mikroglia-Zellen und Oligodendrozyten. In RT-PCR-Experimenten mit mRNA aus durchflusszytometrisch sortierten GLAST-positiven Rückenmarks-Astrozyten lassen sich Transkripte für TRPC1, TRPC2, TRPC3, TRPC4, und TRPC6 nachweisen. Der TRPC2/3/6/7-Agonist 1-oleoyl-2-acetyl-sn-glycerol führt in Wildtyp-, und in TRPC3-defizienten Astrozyten zu cytosolischen Ca2+-Signalen, die sich nicht signifikant unterscheiden. Dennoch war sowohl die Migrations-, als auch die Proliferationsrate von Astrozyten aus TRPC3-defizienten Mausen signifikant reduziert. Neben 1-oleoyl-2-acetyl-sn-glycerol führte auch der TRPC4/5-Agonist EnglerinA zu einem cytosolischen Ca2+-Anstieg in den Astrozyten. Das EnglerinA-induzierte Ca2+-Signal war in TRPC4-defizienten Astrozyten signifikant reduziert, was auf eine funktionelle Expression von TRPC4 in den Astrozyten des Rückenmarks der Maus hinweist. Die TRPC4-defizienten Astrozyten zeigten im Vergleich zu Astrozyten aus dem Rückenmark von Wildtyp-Mäusen eine verminderte Proliferationsfähigkeit, wohingegen die Migrationsfähigkeit unverändert war. Astrozyten aus TRPC1-defizienten Mäusen zeigten im Vergleich zu Wildtyp-Zellen eine erhöhte basale cytosolische Ca2+-Konzentration, sowie einen signifikant erhöhten Ca2+-Anstieg nach Applikation von EnglerinA. Da heteromere TRPC1/TRPC4-Kanäle eine geringere Ca2+-Permeabilität als homomere TRPC4-Kanäle aufweisen, deutet dieses Ergebnis darauf hin, dass TRPC1 in Astrozyten des Rückenmarks heteromere Kanäle mit TRPC4 bildet. Zusammenfassend zeigt die vorliegende Arbeit, dass Astrozyten aus dem Rückenmark der Maus funktionelle 1-oleoyl-2-acetyl-sn-glycerol- (TRPC2/3/6/7) und EnglerinA-aktivierte (TRPC1/4) Ca2+-permeable Kationenkanäle exprimieren, die an der Ca2+-Homöostase sowie an der Migration (TRPC3) und Proliferation (TRPC3 und TRPC4) der Zellen beteiligt sind.Summary The role of TRPC-channels in spinal cord astrocytes The present work deals with the characterization of transient receptor potential (TRP) ion channels in primary astrocytes from the mouse spinal cord using immunocytochemical staining, migration and proliferation assays, as well as fluorometric measurements of the cytosolic Ca2+-concentration (calcium imaging). The most numerous cell populations in mouse spinal cord cultures are astrocytes, microglial cells and oligodendrocytes. Transcripts for TRPC1, TRPC2, TRPC3, TRPC4, and TRPC6 can be detected in RT-PCR experiments with mRNA from flow cytometrically sorted GLAST-positive spinal cord astrocytes. The TRPC2/3/6/7 agonist 1-oleoyl-2-acetyl-sn-glycerol leads to cytosolic Ca2+-signals in wild-type and TRPC3-deficient astrocytes that do not differ significantly. Nevertheless, both the migration and proliferation rates of astrocytes from TRPC3-deficient mice were significantly reduced. In addition to 1-oleoyl-2-acetyl-sn-glycerol, the TRPC4/5 agonist EnglerinA also led to a cytosolic Ca2+-increase in astrocytes. EnglerinA-induced Ca2+-signal was significantly reduced in TRPC4-deficient astrocytes, indicating functional expression of TRPC4 in mouse spinal cord astrocytes. The TRPC4-deficient astrocytes showed reduced proliferation ability compared to astrocytes from the spinal cord of wild-type mice, whereas migration ability was unchanged. Compared to wild-type cells, astrocytes from TRPC1-deficient mice showed an increased basal cytosolic Ca2+-concentration, as well as a significantly increased Ca2+-increase after application of EnglerinA. Since heteromeric TRPC1/TRPC4 channels have lower Ca2+-permeability than homomeric TRPC4 channels, this result suggests that TRPC1 forms heteromeric channels with TRPC4 in spinal cord astrocytes. In summary, the present work shows that astrocytes from the mouse spinal cord express functional 1-oleoyl-2-acetyl-sn-glycerol (TRPC2/3/6/7) and englerinA-activated (TRPC1/4) Ca2+-permeable cation channels, which are involved in Ca2+-homeostasis as well as in cell migration (TRPC3) and proliferation (TRPC3 and TRPC4)

From Despair to Hope: First Arabic Experience of 177Lu-PSMA and 161Tb-PSMA Therapy for Metastatic Castration-Resistant Prostate Cancer

The objective of this retrospective study is to assess the effectiveness and safety of two beta-emitting prostate-specific membrane antigen (PSMA) radioligands, [177Lu]Lu and [161Tb]Tb, in heavily treated patients with metastatic castration-resistant prostate cancer (mCRPC). A total of 148 cycles of beta-emitting PSMA radioligand therapy were given to 53 patients at a specialized cancer care center in Amman, Jordan. This treatment was offered following the exhaustion of all prior treatment modalities. Approximately half of the cases (n = 26) demonstrated an initial partial response to PSMA radioligand therapy. Moreover, roughly one-fourth of the patients (n = 13) exhibited a sustained satisfactory biochemical response, which qualified them to receive a total of six PSMA radioligand therapy cycles and maintain continued follow-up for additional treatment cycles. This was reflected by an adequate prostate-specific antigen (PSA) decline and a concomitant partial response evident on [68Ga]Ga-PSMA positron emission tomography/computed tomography imaging. A minority of patients (n= 18; 34%) experienced side effects. Generally, these were low-grade and self-limiting toxicities. This study endorses previous research evidence about PSMA radioligand therapy’s safety and efficacy. It also provides the first clinical insight from patients of Arab ethnicity. This should facilitate and promote further evidence, both regionally and internationally

Shedding light on the still fuzzy relationship between intelligence and complex problem solving : the role of process measures

Intelligence and complex problem solving (CPS) are well researched constructs that play an important role in educational science and psychology. The significance of these two constructs is based on their close relationship and significant prediction of success in a variety of important real-life outcomes, such as scholastic achievement, achievement in university, and job performance. Regarding the relationship between intelligence and CPS, the two constructs are closely related at the theoretical level. However, despite extensive research, the empirical relationship between intelligence and CPS has not been conclusively clarified. Therefore, the aim of the present dissertation project was to investigate the factors that influence the strength of the association between the two constructs and to examine observable patterns of behavior in which intelligence manifests itself when solving complex problems. As CPS assessment tools are computer-based and interactive, they allow to extract log-file data of students’ problem-solving process from which meaningful patterns of observable behavior can be isolated. Such observable behaviors can be thought of as indicators of cognitive processes and, based on this assumption, can be used to clarify the intelligence-CPS relationship. In the present dissertation project, three studies were conducted to accomplish the aforementioned goal. In a fourth study, a very time-efficient screening instrument to assess an indicator of general intelligence was evaluated and a parallel form was developed, thus expanding the possibilities of intelligence assessment in (large-scale) studies when time is scarce. In the first study, we investigated the Elshout-Raaheim hypothesis (Leutner, 2002; see Elshout, 1987; Raaheim, 1988), which predicts a curvilinear moderating effect of prior knowledge on the relationship between intelligence and CPS, such that correlation coefficients follow an inverted U-shaped pattern. Across a series of five CPS tasks, we hypothesized that prior knowledge would increase from task to task. To test this hypothesis, we considered the relative frequency of CPS exploration behavior to vary-one-thing-at-a-time (VOTAT) in individual CPS tasks as an indicator of prior (strategic) knowledge. The study revealed two main findings: First, the predicted increase in prior knowledge in the knowledge acquisition phase was supported by our data. Second, the pattern of intelligence-CPS correlation coefficients followed an inverted U-shaped pattern in the knowledge acquisition phase and the knowledge application phase of the CPS assessment tool, as predicted. Our findings of an inverted U-shaped pattern of correlation coefficients suggest that intelligence plays a more important role in solving complex problems when participants have acquired medium levels of prior knowledge, and a less important role when participants have acquired either rather low or rather high levels of prior knowledge. In the second study, we examined students’ strategic exploration behavior with regard to eigendynamic effects. Eigendynamic effects are an important characteristic of CPS and can be described as increases or decreases in outcome variables over time without any actions taken by the participant. Specifically, we investigated for the first time the strategic behavior to identify eigendynamic effects in an early exploration step, which is an effective strategic behavior if the system comprises different types of effects (i.e., eigendynamic effects along with other effects). The examined strategic behavior predicted the performance in both CPS phases for the respective tasks and for the set of tasks. Moreover, the mediation models showed that intelligence manifests itself in the strategic behavior to identify eigendynamics early, going hand in hand with higher CPS performance in the knowledge acquisition phase. Regarding the knowledge application phase, the pattern of results suggests that more intelligent students achieved higher CPS performance scores by adequately identifying eigendynamics, but regardless of whether they did so in an early or later exploration step. In the third study, we investigated the effectiveness (i.e., consistent use of VOTAT) and efficiency (i.e., number of non-necessary exploration steps) of students’ exploration behavior in CPS tasks and its relation to intelligence and CPS performance. In a first, exploratory analysis of students’ exploration behavior, we found an increasingly consistent use of VOTAT across the sequence of tasks, corresponding to previous studies. Going beyond previous studies, we showed an increasingly efficient strategy use across tasks. Using a person-centered approach, we found four distinct (latent) classes of students. With respect to these classes, the pattern of results highlights the importance of effectiveness (indicated by VOTAT) for successful problem solving and its relationship to intelligence. However, classes of students who explored effectively, but either more or less efficiently, showed comparable intelligence and CPS test scores. Thus, a pattern of increasingly efficient exploration behavior across tasks was found, but the relationship of efficiency to CPS performance and intelligence requires further research. The fourth study focused on the evaluation and extension of a very time-efficient intelligence screening instrument that can be administered in just three minutes, the mini q (Baudson & Preckel, 2016). Time-efficient and well-evaluated intelligence screenings are important instruments in extensive research projects. Specifically, we examined the test characteristics of the mini-q and introduced a new parallel version, the mini-q B. The distributions of the sum scores of the two test versions indicated discrimination between individuals of different ability and were substantially correlated with each other. With respect to validity, we found correlations with another intelligence test and the GPA that were partially consistent with our assumptions. In summary, the results are promising and indicate the suitability of the mini-q and its parallel version as intelligence screening instruments. Taken together, the results of this dissertation project helped to clarify the ambiguous relationship between intelligence and CPS and to expand the potential applications of a very time-efficient intelligence screening instrument. With regard to the intelligence-CPS relationship, both moderating effects, which influence the strength of the association, and mediating effects, which illustrate how intelligence manifests itself in observable patterns of behavior when solving complex problems, were demonstrated. In addition, the relevance and great potential of log-file data to provide insight into the cognitive processes of problem solvers were demonstrated, helping to clarify the relationship between intelligence and CPS.Keine SicherheitIntelligenz und komplexes Problemlösen (KPL) gelten als gut erforschte Konstrukte mit hoher Relevanz für die Bildungswissenschaften und die Psychologie. Die Bedeutung dieser beiden Konstrukte beruht auf ihrem Zusammenhang mit dem Erfolg in zentralen Lebensbereichen wie Schul- und Studienleistungen und beruflichem Erfolg. Auf theoretischer Ebene sind die beiden Konstrukte eng miteinander verknüpft. Trotz zahlreicher Studien ist der empirische Zusammenhang zwischen Intelligenz und KPL jedoch nicht abschließend geklärt. Ziel dieses Dissertationsprojektes war es daher, Faktoren zu untersuchen, die die Stärke des Zusammenhangs zwischen den beiden Konstrukten beeinflussen, und beobachtbare Verhaltensmuster zu identifizieren, in denen sich Intelligenz beim Lösen komplexer Probleme manifestiert. Da KPL-Testinstrumente in der Regel computergestützt und interaktiv sind, ermöglichen sie die Extraktion von Logfile-Daten des Problemlösungsprozesses. Aus diesen Protokolldaten können beobachtbare Verhaltensmuster isoliert werden, die als Indikatoren für kognitive Prozesse interpretiert werden können und somit zur Klärung der Beziehung zwischen Intelligenz und KPL beitragen. Im Rahmen dieses Dissertationsprojektes wurden drei Studien zur Untersuchung des Zusammenhangs zwischen Intelligenz und KPL durchgeführt. In einer vierten Studie wurde ein sehr zeiteffizientes Screening-Instrument zur Erfassung eines Indikators der allgemeinen Intelligenz evaluiert und eine Parallelform entwickelt, welche die Möglichkeiten der Intelligenzmessung in Studien mit begrenztem Zeitrahmen erweitert. In der ersten Studie untersuchten wir die Elshout-Raaheim-Hypothese (Leutner, 2002; siehe Elshout, 1987; Raaheim, 1988), die einen moderierenden Effekt des Vorwissens auf den Zusammenhang zwischen Intelligenz und KPL in Form eines umgekehrt U-förmigen Musters der Korrelationskoeffizienten vorhersagt. Dabei nahmen wir an, dass über eine Serie von fünf KPL-Aufgaben das Vorwissen von Aufgabe zu Aufgabe zunehmen würde. Um diese Hypothese zu testen, betrachteten wir als Indikator für das (strategische) Vorwissen die relative Häufigkeit des KPL-Explorationsverhaltens, jeweils nur eine Variable zu variieren und alle anderen konstant bei null zu halten (Engl.: vary-one-thing-at-a-time; VOTAT) in einzelnen KPL-Aufgaben. Die Analysen zeigten, dass das strategische Vorwissen in der Phase des Wissenserwerbs wie erwartet zunahm. Darüber hinaus folgt das Muster der Korrelationskoeffizienten zwischen Intelligenz und KPL in der Phase des Wissenserwerbs und in der Phase der Wissensanwendung des KPL-Messinstruments hypothesenkonform einer umgekehrt U-förmigen Kurve. Unsere Ergebnisse eines umgekehrt U-förmigen Musters der Korrelationskoeffizienten deuten darauf hin, dass die Intelligenz eine wichtigere Rolle bei der Lösung komplexer Probleme spielt, wenn die Teilnehmenden ein mittleres Niveau an Vorwissen erworben haben, und eine weniger wichtige Rolle, wenn die Teilnehmenden entweder ein eher niedriges oder ein eher hohes Niveau an Vorwissen erworben haben. In der zweiten Studie wurde das strategische Explorationsverhalten im Hinblick auf eigendynamische Effekte untersucht. Eigendynamische Effekte sind ein wichtiges Merkmal von KPL und können als Zunahme oder Abnahme von Ergebnisvariablen in Abhängigkeit von der Zeit beschrieben werden. Zum ersten Mal wurde das strategische Verhalten untersucht, eigendynamische Effekte in einem frühen Explorationsschritt zu identifizieren, ein effektives Vorgehen, wenn das System verschiedene Arten von Effekten enthält (d. h. eigendynamische Effekte zusammen mit anderen Effekten). Das untersuchte strategische Verhalten sagte die Leistung in beiden KPL-Phasen für die jeweiligen Aufgaben und für das Set an Aufgaben voraus. Darüber hinaus zeigten die Mediationsmodelle, dass sich Intelligenz in der strategischen Verhaltensweise, eigendynamische Effekte in einem frühen Explorationsschritt zu identifizieren, manifestierte, was mit einer höheren KPL-Leistung in der Wissenserwerbsphase einherging. In Bezug auf die Phase der Wissensanwendung deutete das Ergebnismuster darauf hin, dass intelligentere Schülerinnen und Schüler höhere KPL-Leistungen erzielten, indem sie Eigendynamik adäquat identifizierten, aber unabhängig davon, ob sie dies zu einem früheren oder einem späteren Zeitpunkt taten. In der dritten Studie untersuchten wir die Effektivität (d. h. die konsistente Verwendung von VOTAT für jede Eingabevariable) und die Effizienz (d. h. die Anzahl unnötiger Explorationsschritte über die einmalige Verwendung von VOTAT für jede Eingabevariable hinaus) des Explorationsverhaltens bei KPL-Aufgaben und deren Beziehung zur Intelligenz und KPL-Leistung. In einer ersten explorativen Analyse des Explorationsverhaltens fanden wir eine zunehmend konsistente Nutzung von VOTAT über die Aufgaben hinweg. Darüber hinaus und in Erweiterung der aktuellen Forschung fanden wir eine zunehmend effiziente Strategieanwendung. Mit Hilfe eines personenzentrierten Ansatzes konnten vier verschiedene (latente) Klassen von Schülerinnen und Schülern identifiziert werden. In Bezug auf diese Klassen unterstreicht das Ergebnismuster die Bedeutung der Effektivität (gemessen durch VOTAT) für erfolgreiches Problemlösen und ihre Beziehung zur Intelligenz. Es wurden jedoch vergleichbare Intelligenz- und KPL-Leistungen zwischen den Klassen von Schülerinnen und Schülern gefunden, die effektiv, aber mehr oder weniger effizient explorierten. Zusammenfassend wurde ein zunehmend effizienteres Explorationsverhalten festgestellt, dessen Zusammenhang mit Intelligenz und KPL-Leistung weiterer Untersuchungen bedarf. Die vierte Studie konzentrierte sich auf die Evaluation und Konstruktion einer neuen Parallelversion eines sehr zeiteffizienten Screening-Instruments zur Erfassung eines Indikators der allgemeinen Intelligenz in nur drei Minuten, dem mini-q (Baudson & Preckel, 2016). Die Verteilungen der Summenwerte beider Testversionen wiesen auf eine Diskrimination unterschiedlich leistungsstarker Personen hin und korrelierten signifikant miteinander. Hinsichtlich der Validität fanden wir Korrelationen mit einem anderen Intelligenztest und der Abiturnote, die teilweise mit unseren Annahmen übereinstimmten. Die Ergebnisse bezüglich des mini-q und dessen Parallelform lassen sich als vielversprechend zusammenfassen und weisen auf ihre Eignung als Intelligenzscreening-Instrumente hin. Insgesamt haben die Ergebnisse dieses Dissertationsprojektes dazu beigetragen, den Zusammenhang zwischen Intelligenz und KPL weiter aufzuklären und die Anwendungsmöglichkeiten eines Screening-Instruments zur Erfassung der allgemeinen Intelligenz zu erweitern. Hinsichtlich des Zusammenhangs zwischen Intelligenz und KPL konnten sowohl moderierende Effekte, die die Stärke des Zusammenhangs beeinflussen, als auch mediierende Effekte, die verdeutlichen, wie sich Intelligenz in beobachtbaren Verhaltensmustern beim Lösen komplexer Probleme manifestiert, nachgewiesen werden. Weiterhin wurde die Relevanz und das große Potenzial von Logfile-Daten aufgezeigt, die Einblicke in die kognitiven Prozesse von Problemlösenden ermöglichen und damit zur Aufklärung des Zusammenhangs zwischen Intelligenz und KPL beitragen