bluuebunny/crossref_metadata_2025 huggingface dataset:
Untersuchungen zum Lambertschen Cosinusgesetz an nichtabsorbierenden feingepulverten Stoffen
Authors: Kortüm G. , Hamm R.
Published: August 2023

An vier Weißstandard‐Pulverpreßlingen wird die Flächenhelligkeit bei verschiedenen Wellenlängen in Abhängigkeit von Einfalls‐ und Beobachtungswinkel gemessen. Sie ergibt sich in allen Fällen im Gegensatz zum Lambert‐Gesetz als nicht konstant bezüglich des Beobachtungswinkels, die Abweichungen vom Lambert‐Gesetz werden bei großen Winkeln systematisch größer. Bei hartgepreßten, aber glanzfreien Proben steigt die Flächenhelligkeit mit dem Beobachtungswinkel an, außer bei kleinen Einfallswinkeln. Der Anstieg ist für Medien mit kleiner Brechzahl wesentlich stärker als für solche mit großer Brechzahl. Diese Beobachtung kann mit der Bouguerschen Elementarspiegelhypothese und den Fresnelschen Formeln qualitativ gedeutet werden. Für die Richtigkeit der Bouguerschen Vorstellungen über das Zustandekommen der “diffusen Reflexion” spricht ferner die Beobachtung von Glanzspitzen bei Proben, die mit polierten Stempeln stark gepreßt wurden. Die Bouguersche Elementarspiegelhypothese reicht jedoch nicht aus, die diffuse Reflexion quantitativ zu beschreiben.

Lockere Pulveroberflächen zeigen mit zunehmendem Beobachtungswinkel fallende Flächenhelligkeitskurven, die durch Abschattungseffekte zustande kommen. Bei feinerem Korn ist die Abschattung gering, der Fresnel‐Anstieg der Flächenhelligkeitskurven tritt deutlicher hervor. Die Annahme, die Reflexion werde allgemein mit kleinerer Korngröße diffuser, ist nicht richtig. Die Messungen zeigen, daß stets Abweichungen vom Lambertschen Gesetz auftreten und daß das Lambert‐Gesetz unter geeigneten Bedingungen höchstens für kleine Einfalls‐ und Beobachtungswinkel näherungsweise erfüllt ist, insbesondere dann, wenn die Brechzahl des Pulvers genügend groß ist. Der “diffusen Reflexion” nach Lambert überlagern sich stets reguläre Anteile. Es liegt nahe, anzunehmen, daß ein die experimentellen Beobachtungen beschreibendes Gesetz Materialeigenschaften wie Brechzahl und Korngröße berücksichtigen muß.
Gasförmiges Quecksilber unter hohem Druck als “Halbleiter”
Authors: Schmutzler R. , Hensel F. , Franck E. U.
Published: August 2023

Die elektrische Leitfähigkeit gasförmigen Quecksilbers wurde oberhalb der kritischen Temperatur von 1490°C bei Drucken zwischen 1200 und 2100 bar gemessen. Dadurch wird der früher [2] erfaßte Bereich zu niedrigen Dichten erweitert. Die Leitfähigkeit des Gases ist damit im Dichtebereich zwischen 2 und 6 g/cm3 bekannt. Sie steigt mit dieser Dichtezunahme von 10−4 auf 10+2 Ω−1 cm−1. Dies ist ein Beispiel für einen stetigen übergang vom nichtleitenden zum metallisch leitenden Zustand. Die Aktivierungsenergie der Leitfähigkeit wurde errechnet. Sie sinkt mit steigender Dichte und ist bei 5 g/cm3 und dar‐über nur noch wenig von Null verschieden.
Das Kristallisieren und Schmelzen von Hochpolymeren
Authors: Wunderlich Bernhard
Published: August 2023

Die Kristallstruktur von linearen Hochpolymeren wird durch ein Minimum in der freien Energie charakterisiert, das von der intermolekularen Wechselwirkungsenergie und der intramolekularen Konformationsenergie abhängt. Vor der Kristallisation muß Keimbildung stattfinden. Im Falle des Kristallisierens aus Schmelze oder Lösung bei geringer Unterkühlung führt dies zum intramolekularen Faltkeim, bei großer Unterkühlung und der damit verbundenen geringeren Kettenbeweglichkeit kann intermolekulare Fransenmizellenkeimbildung erwartet werden. Analog ist eine intermolekulare Kristallkeimbildung beim Kristallisieren während der Polymerisation aus den als Zwischenprodukt auftretenden Oligomeren und auch eine intramolekulare Kristallkeimbildung bei geringer Oligomerenkonzentration möglich. Die endgültigen Festkörperstrukturen, die sich je nach Kettenkonformation als mehr oder weniger glasig amorph, gefaltet, gestreckt, oder fransenmizellenähnlich beschreiben lassen, zeigen ein grundsätzlich verschiedenes Schmelzverhalten. Gleichgewichtsthermodynamik kann nur das langsame Schmelzen der gestrecktkettigen Kristalle beschreiben. Beim schnellen Heizen treten Überhitzungserscheinungen auf. Die metastabilen, kleinen Kristalle mit oder ohne Kettenfaltung zeigen Reorganisation und Rekristallisation beim langsamen Aufheizen.
Resonanz‐ und Relaxationsabsorption von Polymeren zwischen 1010 und 1012 Hz in Abhängigkeit vom Ordnungsgrad der Struktur
Authors: Amrhein E.
Published: August 2023

Der Zusammenbruch der Fernordnung in Gläsern und partiell kristallinen Stoffen bewirkt eine Abschwächung der Auswahlregeln für die dielektrische Absorption, so daß auch niederfrequente Gitterschwingungen mit dem elektromagnetischen Feld wechselwirken können. Dadurch tritt zwischen 1010 und 1013 Hz eine breite Absorption auf, die stark vom Ordnungsgrad der Struktur abhängt und für alle amorphen Stoffe charakteristisch ist. Messungen an einfachen polaren und unpolaren Polymeren in Abhängigkeit vom Kristallanteil und von der Temperatur haben geholfen, den Mechanismus der Absorption zu klären. Sie wird als „fehlordnungs‐induzierte Einphononenabsorption” gedeutet. – Am langwelligen Ende schließt sich eine temperaturabhängige Mehrphononenabsorption an. Um beide Mechanismen zu trennen, wurde die Temperaturabhängigkeit der 3‐Phononenabsorption theoretisch und experimentell untersucht. Bis zu Mikrowellenfrequenzen ist noch ein Anteil temperaturunabhängiger Einphononenabsorption erkennbar. Hinweise auf eventuelle Relaxationsprozesse wurden nicht gefunden.
Nachkristallisation und Aufschmelzen, ausgelöst durch Diffusion von Lösungsmitteln in Hochpolymeren
Authors: Fuhrmann J. , Driemeyer M. , Rehage G.
Published: August 2023

Durch Diffusion niedrigmolekularer Substanzen in teilkristalline Hochpolymere können morphologische Änderungen ausgelöst werden, die sich dem Diffusionsvorgang überlagern. In der Regel ist dann der Materietransport nicht mehr durch die Fickschen Gesetze zu beschreiben (anomale Diffusion).

Anhand von interferometrisch ausgeführten Messungen am System Polyäthylen‐o‐Xylol können die ablaufenden Einzelprozesse (Konzentrationsänderung, Nachkristallisation, Aufschmelzen und Auflösen) getrennt diskutiert werden. Es wird gezeigt, daß die morphologischen Zustandsänderungen den Diffusionsvorgang steuern können.
Strukturänderungen während der Polymerisation im festen Zustand
Authors: Wegner G. , Munoz‐Escalona A. , Fischer E. W.
Published: August 2023

Polymerisationen im kristallinen Zustand können unter bestimmten Bedingungen zur Erzeugung von makroskopischen Polymer‐Ein‐kristallen mit einer aus gestreckten Ketten bestehenden Morphologie benutzt werden. Die im festen Zustand erzeugten Strukturen unter‐liegen jedoch in Abhängigkeit von der Temperatur ähnlichen Relaxationsprozessen, wie sie auch für andere Umwandlungen bei festen Polymeren bekannt sind. Schlecht geordnete Polymere oder Polymere in glasartigem Zustand als Ergebnis einer Festkörperpolymerisation müssen also nicht unbedingt gegen einen topochemischen Mechanismus der betreffenden Reaktion sprechen.
Elektrosynthese symmetrischer und unsymmetrischer Sulfone
Authors: Knittel D. , Kastening B.
Published: August 2023

Die in einer früheren Arbeit entwickelte Elektrosynthese von Sulfonen durch kathodische Reduktion von Schwefeldioxid in Gegenwart elektrophiler Substratmoleküle wird im Hinblick auf die Möglichkeit untersucht, durch Anwendung zweier verschiedener organischer Verbindungen unsymmetrische Sulfone, d. h. solche mit verschiedenen Resten R — SO2 — R′, zu synthetisieren. Es wird gezeigt daß durch geeignete Reaktionsbedingungen (Temperatur, Art der substituierbaren Gruppe und besonders die Regelung der Konzentration bzw. Dosierung der beiden organischen Verbindungen) das unsymmetrische Sulfon bei befriedigenden Ausbeuten nahezu selektiv, d. h. nahezu ohne gleichzeitige Bildung der beiden symmetrischen Sulfone, erhalten werden kann.
Elektrodenprozesse von Sauerstoff und Wasserstoffperoxid an Platin, Silber und Kohlenstoff
Authors: Březina M.
Published: August 2023

Der Mechanismus der Sauerstoffreduktion und des Wasserstoffperoxidzerfalls wurde an Silber, Platin und Kohlenstoff‐Elektroden mit Hilfe der voltametrischen Kurven untersucht. Eine wichtige Rolle bei diesen Vorgängen spielt die Vorbereitung der Elektrodenoberfläche. Zum Studium des Wasserstoffperoxidzerfalls am Silber wurde auch die Ring‐Scheiben‐Elektrode verwendet. An der aktiven Silberoberfläche ist die Geschwindigkeit des Wasserstoffperoxidzerfalls vom Stofftransport zum Katalysator abhängig. An der mit Paraffinöl gebundenen Kohlenstoffpastenelektrode konnte eine Elektrogenerierung des Superoxidanions beobachtet werden. Die Erniedrigung der Überspannung bei der Sauerstoffreduktion an dieser Elektrode wurde auch zur Bewertung der elektrochemischen Aktivität verschiedener Kohlensorten ausgenützt. Die Sauerstoff‐ bzw. Wasserstoffperoxidreduktion kann durch Zugabe von Hämin in die Grundlösung oder in die Pastenelektrode katalysiert werden.
Tunneleffekte bei der spektralen Sensibilisierung an hochdotierten ZnO‐Elektroden
Authors: Pettinger B. , Schöppel H.‐R. , Gerischer H.
Published: August 2023

Aus der Potentialabhängigkeit oxidativer Tunnelströme, hervorgerufen durch Elektronenübergang aus dem Grundzustand von Farbstoffmolekülen ins Leitungsband von ZnO, läßt sich beweisen, daß die angeregten Niveaus der Sensibilisatoren energetisch auf der Höhe des Leitungsbandes liegen.

Bei der Elektroneninjektion aus angeregten Farbstoffmolekulen treten sofort Oxidationsprodukte auf, die sich an hochdotierten Elektroden durch einen Reduktionsstrom regenerieren und nachweisen lassen. Dieser kathodische Strom kommt durch tunnelnde Leitungselektronen zustande. Damit ist der Elektronenübertragungsmechanismus für die Sensibilisierung in diesem System bewiesen.

An hochdotierten ZnO‐Elektroden wird in Konkurrenz zum Elektronenübergang ein Teil der angeregten Farbstoffmoleküle durch Energieübertragung auf Leitungselektronen (Intrabandanregung) desaktiviert. Dieser Löschprozeß für die angeregten Sensibilisatormoleküle reduziert den Sensibilisierungsstrom.
Studies of Silver(I) Solvation in Binary Solvent Mixtures Containing Dimethyl Sulphoxide: II. NMR Investigations of the Shift in the Preferential Solvation of Silver Ions from Water to DMSO
Authors: Clausen A. , El‐Harakany A. A. , Schneider H.
Published: August 2023

Ag(I) is more strongly solvated in dimethyl sulphoxide than in water. Evidence is presented from NMR and electrochemical work that Ag(I) is preferentially hydrated in dilute aqueous solutions of dimethyl sulphoxide. With increasing concentration of dimethyl sulphoxide the preferential solvation of Ag(I) is shifted from water to dimethyl sulphoxide. This behaviour is related to the characteristic properties of the binary solvent system.
Dynamic Structure and Ion Solvation in Associated Liquids
Authors: Breitschwerdt K. G. , Wolz H.
Published: August 2023

The dynamic n‐state model is based on time‐dependent transport coefficients and applied to the ultrasonic absorption in solutions of simple ions in water, liquid ammonia, and methanol. The absorption measurements were made over a wide range of temperatures at frequencies between 5 and 100 MHz. The characteristic differences of the thermodynamic parameters, the relaxation times, the molar volumes, and the solvation numbers are discussed for the liquids and ions investigated.
Co‐designing an online treatment decision aid for men with low‐risk prostate cancer: Navigate
Authors: Schofield Penelope , Hyatt Amelia , White Alan , White Fiona , Frydenberg Mark , Chambers Suzanne , Gardiner Robert , Murphy Declan G. , Cavedon Lawrence , Millar Jeremy , Richards Natalie , Murphy Barbara , Juraskova Ilona
Published: August 2023

Objectives

To develop an online treatment decision aid (OTDA) to assist patients with low‐risk prostate cancer (LRPC) and their partners in making treatment decisions.

Patients and methods

Navigate, an OTDA for LRPC, was rigorously co‐designed by patients with a confirmed diagnosis or at risk of LRPC and their partners, clinicians, researchers and website designers/developers. A theoretical model guided the development process. A mixed methods approach was used incorporating (1) evidence for essential design elements for OTDAs; (2) evidence for treatment options for LRPC; (3) an iterative co‐design process involving stakeholder workshops and prototype review; and (4) expert rating using the International Patient Decision Aid Standards (IPDAS). Three co‐design workshops with potential users (n = 12) and research and web‐design team members (n = 10) were conducted. Results from each workshop informed OTDA modifications to the OTDA for testing in the subsequent workshop. Clinician (n = 6) and consumer (n = 9) feedback on usability and content on the penultimate version was collected.

Results

The initial workshops identified key content and design features that were incorporated into the draft OTDA, re‐workshopped and incorporated into the penultimate OTDA. Expert feedback on usability and content was also incorporated into the final OTDA. The final OTDA was deemed comprehensive, clear and appropriate and met all IPDAS criteria.

Conclusion

Navigate is an interactive and acceptable OTDA for Australian men with LRPC designed by men for men using a co‐design methodology. The effectiveness of Navigate in assisting patient decision‐making is currently being assessed in a randomised controlled trial with patients with LRPC and their partners.
Quantification and holistic quality evaluation of Wulingzhi extract by UHPLC–Q‐Orbitrap–HRMS coupled with chemometric approaches
Authors: Wang Anqi , Li Zheng , Wang Jinghui , Liu Haolong , Fu Xintong , Chen Yougen , Guo Hongzhu
Published: August 2023

The excreta of Trogopterus xanthipes (“Wulingzhi” in Chinese, WLZ) is a well‐known traditional Chinese medicine. It has been used for centuries to treat amenorrhea, menstruation and postpartum abdominal pain. However, a systematic quality study on WLZ chemical markers has yet to be conducted. This study aimed to establish an ultra‐high‐performance liquid chromatography coupled with a hybrid quadruple extraction Orbitrap high‐resolution mass spectrometry (UHPLC–Q‐Orbitrap–HRMS) method for the simultaneous quantitative determination of 20 compounds in 53 batches of WLZ; the method rapidly and sensitively determined the 20 plant‐ or animal‐derived compounds. Firstly, the proposed approach was validated to satisfy the method’s linearity, detection limits, precision, repeatability, stability and accuracy. Subsequently, multivariate analysis was used to identify correlations between the samples and feed, processing and regions. Finally, this method was used to further identify chemical markers for quality control in combination with chemometrics. This is the first report on pinusolide, betaine, hippuric acid, 4‐oxorentinoic acid, 15‐methoxypinusolidic acid and 4‐oxoisotrentinoin in WLZ; the quality of WLZ became homogeneous after processing with vinegar (V‐WLZ). Moreover, we screened for potential component markers, including uridine, allantoin, amentoflavone, hippuric acid, 3,4‐dihydroxybenzoic acid, pinusolide, quercetin and kaempferol. These results were practical and efficient for the chemical clarification of WLZ and V‐WLZ.
Safety and efficacy of neoadjuvant chemoradiotherapy with moderately hypofractionated intensity‐modulated radiotherapy for resectable pancreatic cancer: A prospective, open‐label, phase II study
Authors: Masui Toshihiko , Nagai Kazuyuki , Anazawa Takayuki , Kasai Yosuke , Yogo Akitada , Yoshimura Michio , Mizowaki Takashi , Uza Norimitsu , Fukuda Akihisa , Matsumoto Shigemi , Kanai Masashi , Isoda Hiroyoshi , Kawaguchi Yoshiya , Uemoto Shinji , Hatano Etsuro
Published: August 2023

Background

Resectable pancreatic cancer (RPC) is potentially resectable on admission, and the impact of neoadjuvant therapy on these tumors is controversial. Moreover, the safety and efficacy of neoadjuvant chemoradiotherapy with moderately hypofractionated intensity‐modulated radiation therapy (NACIMRT) for RPC have not been studied. Here, we conducted a phase II study to evaluate the safety and efficacy of hypofractionated NACIMRT for RPC.

Methods

A total of 54 RPC patients were enrolled and treated according to the study protocol. We used moderately hypofractionated (45 Gy in 15 fractions) IMRT with gemcitabine to shorten the duration of radiotherapy and reduce gastrointestinal toxicity. The primary endpoint was overall survival (OS), and we subsequently analyzed the microscopically margin‐negative resection (R0) rate, disease‐free survival (DFS), and histologic effects and safety of NACIMRT.

Results

Median OS for the cohort was 40.0 months. Forty‐two patients (77.8%) underwent pancreatectomy after NACIMRT. Median DFS was 20.3 months. The R0 resection rate was 95.2% (40/42) per protocol and 85.2% (46/54) for the cohort. There were no intervention‐related deaths during the study period. Local treatment response, as assessed by the CAP classification, showed no residual tumor in 4.8% of patients. Overall, 23.9% of patients experienced CTCAE grade 3 or 4 during NACIMRT. Adjuvant therapy was initiated in 88% of patients undergoing resection. Postoperative complications grade ≥3b on the Clavien–Dindo scale occurred in 4.8% of patients. CA19‐9 level at enrollment was an independent prognostic factor for OS and DFS.

Conclusions

This is the first prospective study of hypofractionated IMRT as neoadjuvant therapy for RPC. Hypofractionated NACIMRT for RPC could be safely introduced with a high induction rate of adjuvant chemotherapy, with an overall survival of 40.0 months.
Effect of 2‐methoxyestradiol treatment on early‐ and late‐stage breast cancer progression in a mouse model
Authors: Peta Kimberly T. , Durandt Chrisna , van Heerden Marlene B. , Joubert Anna M. , Pepper Michael S. , Ambele Melvin A.
Published: August 2023

The prevalence of breast cancer (BC) continues to increase and is the leading cause of cancer deaths in many countries. Numerous in vitro and in vivo studies have demonstrated that 2‐methoxyestradiol (2‐ME) has antiproliferative and antiangiogenic effects in BC, thereby inhibiting tumour growth and metastasis. We compared the effect of 2‐ME in early‐ and late‐stage BC using a transgenic mouse model—FVB/N‐Tg(MMTV‐PyVT)—of spontaneously development of aggressive mammary carcinoma with lung metastasis. Mice received 100 mg/kg 2‐ME treatment immediately when palpable mammary tumours were identified (early‐stage BC; Experimental group 1) and 28 days after palpable mammary tumours were detected (late‐stage BC; Experimental group 2). 2‐ME was administered via oral gavage three times a week for 28 days after initiation of treatment, whereas control mice received the vehicle containing 10% dimethyl sulfoxide and 90% sunflower oil for the same duration as the treatment group. Mammary tumours were measured weekly over the 28 days and at termination, blood, mammary and lung tissue were collected for analysis. Mice with a tumour volume threshold of 4000 mm3 were killed before the treatment regime was completed. 2‐ME treatment of early‐stage BC led to lower levels of mammary tumour necrosis, whereas tumour mass and volume were increased. Additionally, necrotic lesions and anti‐inflammatory CD163‐expressing cells were more frequent in pulmonary metastatic tumours in this group. In contrast, 2‐ME treatment of late‐stage BC inhibited tumour growth over the 28‐day period and resulted in increased CD3+ cell number and tumour necrosis. Furthermore, 2‐ME treatment slowed down pulmonary metastasis but did not increase survival of late‐stage BC mice. Besides late‐stage tumour necrosis, none of the other results were statistically significant. This study demonstrates that 2‐ME treatment has an antitumour effect on late‐stage BC, however, with no increase in survival rate, whereas the treatment failed to demonstrate any benefit in early‐stage BC.
Cost effectiveness of nonpharmacological prevention programs for diabetes: A systematic review of trial‐based studies
Authors: Xiong Yongyi , Huo Zhaohua , Wong Samuel Y. S. , Yip Benjamin H. K.
Published: August 2023

Trial‐based economic value of prevention programs for diabetes is inexplicit. We aimed to review the cost‐effectiveness of nonpharmacological interventions to prevent type‐2 diabetes mellitus (T2DM) for high‐risk people. Six electronic databases were searched up to March 2022. Studies assessing both the cost and health outcomes of nonpharmacological interventions for people at high‐risk of T2DM were included. The quality of the study was assessed by the Consolidated Health Economic Evaluation Reporting Standards 2022 checklist. The primary outcome for synthesis was incremental cost‐effectiveness ratios (ICER) for quality‐adjusted life years (QALYs), and costs were standardized in 2022 US dollars. Narrative synthesis was performed, considering different types and delivery methods of interventions. Sixteen studies included five based on the US diabetes prevention program (DPP), six on non‐DPP‐based lifestyle interventions, four on health education, and one on screening plus lifestyle intervention. Compared with usual care, lifestyle interventions showed higher potential of cost‐effectiveness than educational interventions. Among lifestyle interventions, DPP‐based programs were less cost‐effective (median of ICERs: $27,077/QALY) than non‐DPP‐based programs (median of ICERs: $1395/QALY) from healthcare perspectives, but with larger decreases in diabetes incidence. Besides, the cost‐effectiveness of interventions was more possibly realized through the combination of different delivery methods. Different interventions to prevent T2DM in high‐risk populations are both cost‐effective and feasible in various settings. Nevertheless, economic evidence from low‐ and middle‐income countries is still lacking, and interventions delivered by trained laypersons and combined with peer support sessions or mobile technologies could be potentially a cost‐effective solution in such settings with limited resources.
Preparation of Nitrogen‐Doped Graphene with Hollow Nano‐Hemispheres from FexOy@Fe‐N‐GN: Towards High Capacity and Durable Anode for Li‐Ion Batteries by Chemical Modifications
Authors: Bayram Edip , Sungur Berkay
Published: August 2023

The development of high‐performance Li‐ion battery anodes is closely dependent on understanding the effect of chemical and physical properties of active materials played in the storage mechanism. In this study, mesoporous high surface area nitrogen‐doped graphene (N‐GN) and nitrogen‐doped graphene‐coated nano‐spherical FexOy containing composite (FexOy@Fe‐N‐GN) were synthesized by a bottom‐up solvothermal process using required starting materials. Acid leaching of FexOy@Fe‐N‐GN resulted in a highly microporous structure consisting of a hollow graphene nano‐hemisphere and a large basal plane monoblock structure with 63 % N‐doped graphene and 37 % graphitic N‐doped graphene (Fe‐N‐GN). While N‐GN and FexOy@Fe‐N‐GN exhibited 310 and 571 mAh g−1 reversible capacity, respectively, after 100 cycles, Fe‐N‐GN showed 940 mAh g−1 reversible capacity through >70 % diffusion‐controlled process with beneficially lower intercalation potential below ~0.25 V and 87 % capacity retention demonstrating the impact of the chemical composition and structural properties on the capacity of carbon‐based anodes.
Chiral TPE Foldamers in Macrocycles: Aggregation Enhanced Emission and Circularly Polarized Luminescence
Authors: Wang Yuxiang , Cui Liwen , Wang Yiran , Li Fei , Li Yunzhi , Meng Qi
Published: August 2023

Chiral macrocycles with circularly polarized luminescence (CPL) have attracted increasing attention due to the rigid structure, symmetrical chiral geometry and large luminescence dissymmetry factors (glum). However, most chiral macrocycles are more emissive in solutions but have weakened fluorescence quantum yields (ΦF) in aggregates, limiting their further application. In this paper, chiral macrocycle R/S‐PhTPE was synthesized by combining chiral macrocycle architectonics with Z‐o‐phenyltetraphenylethylene (PhTPE) foldamer. Enhanced solution state emission and characteristic aggregation enhanced emission (AEE) effect can be observed for R/S‐PhTPE due to the folded PhTPE conformation. Macrocycle immobilization and folded conformation endow PhTPE moiety with stable helical conformation. Most importantly, R/S‐PhTPE exhibits opposite CPL signals compared with common chiral TPEs, demonstrating the evident impact of folded conformation. This work reports the first and deep insights into the chiroptical properties of chiral PhTPE foldamers, and will provide a new strategy to tune ΦF and CPL signals of AIE active chiral macrocycles.
The Challenging World of Simple Inorganic Rings: Revisiting Roesky's Ketone and Roesky's Sulfoxide
Authors: Cunha Ana V. , Havenith Remco W. A. , Van Alsenoy Christian , Blockhuys Frank
Published: August 2023

The surprising differences between the experimental solid‐state and calculated gas‐phase structures of 5‐oxo‐1,3,2,4‐dithiadiazole (Roesky's ketone, 1) and 1‐oxo‐1,2,4,3,5‐trithiadiazole (Roesky's sulfoxide, 2), identified and studied in a series of papers published between 2004 and 2010 but then never satisfactorily explained, have been revisited, making use of the more advanced computational possibilities currently available. The previous calculations’ considerable overestimations of the C−S and S−S bond lengths in 1 and 2, respectively, have been partly explained based on the results of periodic calculations and the application of Valence Bond (VB) Theory. In the case of 1, the crystal environment appears to stabilize a structure with a highly polarized C=O bond, which features a C−S bond with considerable double‐bond character – an effect which does not exist for the isolated molecule – explaining the much shorter bond in the solid state. For 2, a similar conclusion can be drawn for the S−S distance. For both compounds, though, packing effects are not the sole source of the differences: the inability of Density Functional Theory (DFT) to properly deal with the electronic structures of these apparently simple main‐group systems remains a contributing factor.
Impact of Truncation on Optoelectronic Properties of Azaborole Helicenes
Authors: Full Julian , Wildervanck Martijn J. , Dillmann Claudia , Panchal Santosh P. , Volland Daniel , Full Felix , Meerholz Klaus , Nowak‐Król Agnieszka
Published: August 2023

Herein, we report configurationally stable singly‐truncated (ST) and structurally flexible doubly‐truncated (DT) helically chiral compounds derived from azabora[7]helicenes by a hypothetical removal of a single or two C=C double bonds. The singly‐truncated constitutional isomers were synthesized from either benzoisoquinoline (BIQ) or phenantherene building blocks and the corresponding biaryls in excellent yields to give azabora[5]helicenes with a pendant phenyl ring at a sterically hindered position. These systems highlight the electronic impact of the nitrogen donor substitution position. The compounds with a disrupted BIQ moiety (STN) possess remarkable photoluminescence quantum yields of up to 0.53 in the solid state and a blue emission in solution with dissymmetry factors of up to ca. 3×10−3. Upon cooling to 79 K all compounds exhibit phosphorescence with lifetimes of up to ca. 0.5 s. A methyl complex of azabora[7]helicene showing excellent configurational stability was used as a chiral inducer embedded in an emissive polymer (F8BT) to produce circularly polarized organic light emitting diodes with an electroluminescence dissymmetry factor gEL of up to 0.54.
Mineralwasser – voll die Härte
Authors: Emden Markus , Hild Pitt , Kallinna Kirsten , Murer Livia
Published: August 2023

Anliegen der in loser Folge erscheinenden Versuche ist es, Impulse für chemische Versuche zu geben, die gefahrlos zu Hause mit haushaltsüblichen Gegenständen durchgeführt werden können. Sie können damit als Quelle für das gemeinsame Ausprobieren mit Kindern dienen, z. B. in Kindergärten oder an Schulen sowie zur Verwendung bei Tagen der offenen Tür. Ein Stückweit sind sie zu verstehen als Antwort auf den oft gehörten Satz: „Ach, Du bist Chemiker/in? Dann mach doch mal eben ein Experiment.“
Intraspecific trait variation and adaptability of Stipa krylovii: Insight from a common garden experiment with two soil moisture treatments
Authors: Liu Yulin , Fan Baijie , Gong Ziqing , He Luoyang , Chen Lei , Ren Anzhi , Zhao Nianxi , Gao Yubao
Published: August 2023

Understanding patterns of intraspecific trait variation can help us understand plant adaptability to environmental changes. To explore the underlying adaptation mechanisms of zonal plant species, we selected seven populations of Stipa krylovii, a dominant species in the Inner Mongolia Steppe of China, and evaluated the effects of phenotypic plasticity and genetic differentiation, the effects of climate variables on population trait differentiation, and traits coordinated patterns under each soil moisture treatment. We selected seeds from seven populations of S. krylovii in the Inner Mongolia Steppe, China, and carried out a soil moisture (2) × population origin (7) common garden experiment at Tianjin City, China, and measured ten plant traits of S. krylovii. General linear analyses were used to analyze how soil moisture and population origin affected each trait variation, Mantel tests were used to analyze population trait differentiation—geographic distance (or climatic difference) relationships, regression analyses were used to evaluate trait‐climatic variable relationships, and plant trait networks (PTNs) were used to evaluate traits coordinated patterns. Both soil moisture and population origin showed significant effects on most of traits. Aboveground biomass, root‐shoot ratio, leaf width, specific leaf area, and leaf nitrogen (N) content were significantly correlated with climate variables under the control condition. Specific leaf area and leaf N content were significantly correlated with climate variables under the drought condition. By PTNs, the hub trait(s) was plant height under the control condition and were aboveground biomass, root length, and specific leaf area under the drought condition. This study indicates that both phenotypic plasticity and genetic differentiation can significantly affect the adaptability of S. krylovii. In addition, soil moisture treatments show significant effects on trait‐climate relationships and traits coordinated patterns. These findings provide new insights into the adaptive mechanisms of zonal species in the semiarid grassland region.
Morphological diversity and altitudinal differentiation of Aethopyga species
Authors: Lu Wenzhu , Shao Shimiao , Zu Lingling , Luo Xu , Duan Yubao
Published: August 2023

The morphological characteristics of birds are an important tool for studying their adaptation and evolution. The morphological evolution of a clade is not only constrained by the phylogenetic relationship, but also influenced by ecological factors and interspecific competition. Aethopyga is a group of small nectar‐eating birds with obvious sexual dimorphism. They have slender and decurved beaks, which reflect their unique diet and foraging mode. Traditional and geometric morphometrics were combined to characterize the body morphology and beak shape of six species of Aethopyga distributed in China. We aim to assess the roles of phylogeny, altitude, and species interactions to morphological evolution. The main distinguishing characteristic among these six species were overall body size, the ratio of body weight, culmen and tarsal length to body length, tail length and wing length, and beak shape (slender/straight vs. thick/decurved). Although these dimensions cannot distinguish all species, they can show a clear distribution trend, and there is a significant Mahalanobis distance between each pair of species. There were no significant phylogenetic signals in morphological traits. The results of PGLS analysis show that altitude is significantly correlated with log‐transformed tarsus length and beak‐shaped PC1 (slender/straight vs thick/decurved dimensions) across the six species analyzed. Mantel test shows that the distance matrix of beak morphological characteristics showed a significant correlation with the altitudinal distance matrix. The results indicated no significant phylogenetic signal in the morphological characteristics of six species. In terms of beak shape, species with greater overlap in elevation distribution have more similar morphological characteristics, that is, less morphological differentiation.
Alpha and beta diversity jointly drive the aboveground biomass in temperate and tropical forests
Authors: Yao Jie , Huang Jihong , Zang Runguo
Published: August 2023

Changes in biodiversity often affect ecosystem functioning. However, most previous biodiversity and ecosystem functioning (BEF) studies have generally been limited to very small spatial grains. Thus, knowledge regarding the biodiversity–ecosystem functioning relationships across spatial scales is lacking. Moreover, the multiscale nature of biodiversity, and specifically β diversity (i.e., spatial heterogeneity in species composition) was still largely missing in BEF studies. Here, using the vegetation and functional trait data collected from four 6‐ha forest dynamics plots (FDPs) in temperate and tropical forests in China, we examine the scale‐dependent relationships between tree diversity and the aboveground biomass (AGB), as well as the roles of species spatial heterogeneity in determining the AGB. In tropical forests, the effect of species richness on AGB decreased with spatial grains, while functional dominance played a stronger role at larger spatial grains. In temperate forests, positive relationship between diversity and AGB occurred at all spatial grains, especially on smaller scales. In both temperate and tropical forests, β diversity was positively correlated with AGB, but weaker than α diversity in determining AGB. Overall, complementarity and selection hypothesis play dominant role in determining AGB in temperate and tropical forests, respectively. The roles of these underlying mechanisms are more pronounced with increasing spatial scales. β diversity, a hitherto underexplored facet of biodiversity, is likely to increase ecosystem functions by species spatial turnover and should not be neglected in BEF explorations. Our findings have practical implications for forest management and demonstrate that biotic heterogeneity plays an important positive role in ecosystem functioning.
Polarization from the perspective of ambivalents: Feeling caught in the social crossfire of the U.S. abortion debate
Authors: Ton Gonneke M. , van Zomeren Martijn , Stroebe Katherine
Published: August 2023

In polarized societal debates, it is often assumed that perceiving polarization leads individuals to take sides (e.g., “pro‐life” or “pro‐choice”). However, perceiving polarization can also make individuals ambivalent because they feel “caught in the social crossfire” of the debate. We conducted a survey study (Ntotal = 863 women) on ambivalents’ perspectives of the U.S. abortion debate. Findings supported the hypothesis that ambivalents’ perceived polarization related positively to their felt ambivalence. This relationship can be explained by their feeling of being “caught in the social crossfire”: they feel torn while also understanding both sides of the debate. Moreover, felt ambivalence was positively related to tendencies toward avoidance of the debate but also toward conciliatory efforts (e.g., to create mutual understanding between the groups). We discuss the implications of these findings for the relationship between perceived polarization and felt ambivalence among ambivalents.
High‐Entropy Oxysulfide for High‐Performance Oxygen Evolution Reactions Electrocatalyst
Authors: Chatterjee Arindam , Ghosh Anamika , Ganguly Dipsikha , Sundara Ramaprabhu , Bhattacharya Subramshu S.
Published: August 2023

Hydrogen energy is considered as a significant clean, green, and renewable energy technology. Oxygen evolution reaction (OER) plays an important role in hydrogen production through overall electrochemical water splitting. Herein, novel transition‐ and rare‐earth metal‐based high‐entropy oxysulfides (HEOS) are synthesized via low‐temperature hydrothermal method to overcome the immiscibility issue of sulfur. HEOS with systematically varying sulfur content are investigated as electrocatalysts in the OER for the first time. To assess the contribution of sulfur toward OER, the electrocatalytic performance of oxysulfides is compared with high‐entropy oxides (not containing sulfur). HEOS with higher sulfur content shows superior electrocatalytic activity and outperforms the high‐entropy oxides. The considerable amount of sulfate left in the structure during electrolysis contributes to the catalytic activity. The HEOS exhibits a reasonable overpotential of 348 mV at a current density of 10 mA cm−2 and outstanding electrochemical stability of 100 h of testing. The extraordinary OER activity of complex HEOS demonstrates its viability in rational design of highly efficient oxysulfide catalyst for overall water‐splitting.
Nexus between financial inclusion and natural resource management: How human development affects the sustainability practices
Authors: Weng Dong , Xia Qionghua
Published: August 2023

There is increasing apprehension surrounding the sustainable governance of natural resources in South Asian nations, where the economy's progress is significantly dependent on these resources. Financial inclusion is a vital determinant in promoting sustainable practices as it pertains to the accessibility and utilization of financial services by all population sectors. Moreover, the field of human development, which encompasses various indicators, including education, healthcare, and living standards, exerts a substantial influence on the formation of societal behaviour and attitudes towards the conservation of resources. This research investigates the correlation between financial inclusion, natural resource management, and human development in South Asian nations from 2008 to 2020. Panel data modelling is used in this study to examine the relationship between the abovementioned variables and evaluate human development's influence on sustainability practices. This study utilizes panel data analysis to examine the complex association between financial inclusion and natural resource management. This study examines the relationship between different levels of human development and adopting sustainable practices within the region. Using the panel data framework facilitates the analysis of both idiosyncratic country‐specific effects and shared patterns observed among the South Asian countries under consideration. The findings of this research offer valuable perspectives on the intricate relationship between financial inclusion, human development, and natural resource management. The results of this study make a valuable contribution to the current body of literature by emphasizing the importance of inclusive financial systems in fostering sustainable practices. Furthermore, these findings provide insight into the influence of human development on the formation of individuals' attitudes and behaviours about the conservation of resources. The implications of these findings are relevant for policymakers and stakeholders who aim to improve sustainability initiatives and promote inclusive economic development in South Asian nations.
Identifying and addressing unmet clinical needs in primary cutaneous B‐cell lymphoma: A consensus‐based paper from an ad‐hoc international panel
Authors: Quaglino Pietro , Pimpinelli Nicola , Zinzani Pier Luigi , Paulli Marco , Pileri Stefano , Berti Emilio , Cerroni Lorenzo , Guitart Joan , Kim Youn H. , Rupoli Serena , Santucci Marco , Simontacchi Gabriele , Vermeer Maarten , Hoppe Richard , Pro Barbara , Swerdlow Steven H. , Barosi Giovanni
Published: August 2023

Primary cutaneous B‐cell lymphomas (PCBCLs) are lymphoproliferative disorders that appear on the skin without evidence of extracutaneous manifestations at the time of diagnosis. There is a lack of evidence‐based guidelines for their clinical management due to the availability of very few large scale studies and controlled clinical trials. Here we present and discuss a series of major unmet clinical needs (UCNs) in the management of PCBCLs by a panel of 16 experts involved in research and clinical practice of PCBCL. The Panel produced recommendations on the appropriateness of the clinical decisions concerning the identified clinical needs and proposed research for improving the knowledge needed to solve them. Recommendations and proposals were achieved by multiple‐step formalized procedures to reach a consensus after a comprehensive analysis of the scientific literature. Recommendations and proposals lay in the domain of classification uncertainties of PCBCL, optimization of diagnosis, optimization of prognosis, optimization of staging and critical issues on therapeutic strategies with particular focus on new treatments. These recommendations are intended for use not only by experts but above all by dermatologists and hematologists with limited experience in the field of PCBCLs as well as general practitioners.
Lessons Learned and Recommendations for the Application of Systems Engineering as an Emerging Discipline in Transportation & Infrastructure Projects
Authors: Hoehne Oliver
Published: August 2023

While systems engineering (SE) has been a well‐established discipline focusing on interdisciplinary systems and engineering management of complex systems over their life cycles, SE is still widely unknown in the U.S. infrastructure industry.

The U.S. has recently passed a $1 trillion infrastructure bill (H.R. 3684), calling for investments in roads, bridges, rail, ports, airports, power, water, broadband, and other major projects. It is the intent of this paper to provide practical guidance to infrastructure owners and operators who are interested in reaping the benefits of applying SE to their transportation and infrastructure projects.

This paper memorializes the lessons learned from over a of decade of real‐world, hands‐on experience of introducing and gradually increasing the application of systems engineering to building the civil infrastructure of the California High‐Speed Rail System (CHSRS), starting with the environmental impact review, preliminary engineering, final design, construction, inspection and testing, and finally the certification and planned handover of 119 miles of civil work and over 225 individual structures to the following track and systems contracts.

As the first three CHSRS civil works construction packages (CP) are currently nearing completion, three new civil work and passenger station procurement contracts have recently been awarded, extending CHSRS to 171 miles and close to 300 structures, including four passenger stations, with additional track and systems, trainset, and train operator contracts planned in the near future.

The extension of the CHSRS presented a timely opportunity to incorporate the SE lessons learned during the first three construction packages and update the systems engineering process requirements for the new CHSRS extension projects going forward. The SE requirements are presented in form of Systems Development Life Cycle (SDLC) requirements and have been prepared as tailored requirements for both civil infrastructure and track and systems contracts.

This paper intends to share the lessons learned and present them as specific and actionable recommendations, providing practical guidance for the application of SE to transportation and/or infrastructure projects.
Democratizing Systems Security
Authors: Dove Rick , Winstead Mark , Dunlap Holy , Hause Matthew , Scalco Aleksandra , Willett Keith , Williams Adam D. , Wilson Beth
Published: August 2023

As systems security joins the top concerns of systems engineering, the availability and affordability of already scarce security expertise presents a resource barrier and raises questions about the nature of competency needed in the systems engineering team. Workshops in 2022 exploring the eleven strategies outlined in the 2021 roadmap for Security in the Future of Systems Engineering revealed one strategy as centrally synergistic with all the other ten: Stakeholder Alignment. Investigating means and effects of aligning stakeholders on security requirements led to the understanding that security expressed as loss‐driven needs and capabilities would be accessible to everyone, independent of how those needs and capabilities would be realized. This article makes a case for achieving stakeholder security alignment as a means to efffectualize security as a foundational perspective in system design and actualize security proficiency in the SE team.
Preventing MBSE Amnesia through Role‐Based Knowledge Management
Authors: Fitzsimmons Sharon
Published: August 2023

The problems of knowledge management (KM) have changed in the last thirty years since its introduction, as evidenced by the decrease in searches for “knowledge management” and the up‐tick in Google trends for searches on “big data.” With the introduction of Web 2.0, the amount of data available within a company has exploded, but a company's technology for navigating that data has not necessarily kept up. Consequently, companies are at high risk for organizational knowledge loss. This is particularly acute in new technologies that suffer from a labor shortage, such as Model‐Based Systems Engineering (MBSE).

To reduce this risk, best practices for knowledge taxonomy and knowledge navigation are explored within this paper. A systematic literature review will generate categorization data for MBSE topics and suggest organization for a Knowledge Management System (KMS) that will facilitate user interaction. Gaps in the current research of MBSE are identified for future research. Future research may also include organizational surveys to evaluate adoption and perceived effectiveness of the recommended best practices.
System Requirements Development Under a Dual‐Prime Contracting Model
Authors: Pearce Paul
Published: August 2023

Developing requirements for a highly coupled complicated system is a challenging prospect for any project. The task gets more complicated if multiple organisations are needed to deliver the required solution. This paper relates the practical experience of ‘dual prime contracting’ where two organisations take the lead for the delivery of a system in response to the requirements of a common customer. The first part of the paper describes real motivations and contractual elements that underpin a dual prime contracting model. The technical body of the paper describes how a single requirement set is allocated and flowed to two prime contractors and introduces the common product breakdown structure. The allocation and flow down of non‐functional transversal requirements is given special treatment. The paper closes with useful insights for dual‐prime contractors, emphasising the value of early planning and preparation of joint collaboration strategies.
Systems Thinking Applied to Higher Education Curricula Development
Authors: London Mark , Rahdar Reza , Jiang Hong , Lin Yuetong
Published: August 2023

Systems Thinking (ST) is a general and yet nebulous term that describes an approach to understanding and working with complexity in the real world. ST seeks to evaluate different behaviors of individual system elements when they operate in isolation as opposed to when they are integrated as part of a larger system and placed within a particular operating environment. The education environment consists of multiple systems with different digital content, learning goals/outcomes that serve different stakeholders including teachers, learners, and administrators. The inherent complexity and interaction among these various educational system elements and functions make this environment a worthy candidate for consideration within the ST context. In this paper we examine the application of ST principles to higher education. Specifically, our study suggests that systems thinking methods and concepts can promote improved outcomes in curricula development with a positive impact on student learning.