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Organochlorides Mediate Oxidation Reactions Induced by Low Dose Ionizing Radiation

In cancer treatment, there exists an acute need to deliver drugs exclusively at the tumor site. This necessity arises from the adverse side effects associated with systemic treatments and the potential utilization of highly cytotoxic drugs. The use of ionizing radiation to trigger the release of chemotherapeutic drugs holds great promise in this regard, both to achieve local, targeted release as well as in the context of combined radiotherapy-chemotherapy approaches. However, a substantial challenge persists across these methodologies: the inherent insensitivity of molecular processes to ionizing radiation at clinically relevant radiation doses. In simpler terms, inducing selective breaking or making of chemical bonds -essential for drug release or activation- is exceedingly difficult at low radiation doses. To date, only a handful of highly specific methods have been reported. In a collaborative project with prof. Antonia Denkova (RST), where we discovered that certain organochloride compounds significantly amplify radiation-induced oxidation, this can be used to initiate release and activation of drugs. Remarkably, our method already demonstrates efficacy with a mere 4 Gy dose of gamma or X-rays, well within the confines of standard clinical radiotherapy doses. J. Liu, T. G. Brevé, B. Xu, P.-L. Hagedoorn, A.G. Denkova, R. Eelkema Abstract The controlled release of drugs using local ionizing radiation presents a promising approach for targeted cancer treatment, particularly when applied in concurrent radio-chemotherapy. In these approaches, radiation-generated reactive species often play an important role. However, the reactive species that can be used to trigger release have low yield and lack selectivity. Here, we demonstrate the generation of highly oxidative species when aqueous solutions containing low concentrations of organochlorides (such as chloroform) are irradiated with ionizing radiation at therapeutically relevant doses. These reactive species were identified as peroxyl radicals, which formed in a reaction cascade between organochlorides and aqueous electrons. We employed stilbene-based probes to investigate the oxidation process, showing double bond oxidation and cleavage. To translate this reactivity into a radiation-sensitive material, we have synthesized a micelle forming amphiphilic block copolymer that has stilbene as the linker between two blocks. Upon exposure to ionizing radiation, the oxidation of stilbene led to the cleavage of the polymer, which induces the dissociation of the block-copolymer micelles and the release of loaded drugs. Dr. Rienk Eelkema Read the publication

13-17 mei | Week van Exhale: Een week vol workshops en evenementen over intimiteit en relaties

Een week vol events en activiteiten rondom sociale connectie en ontspanning! Bij Exhale vinden vier keer per jaar zogenaamde Exhale Weken plaats: een week vol events en activiteiten rondom sociale connectie en ontspanning! De tweede Exhale Week vindt plaats van 13 tot 17 mei en nodigt je uit om intimiteit en relaties te verkennen tijdens een week vol open, eerlijke en leerzame evenementen en workshops. Alleen al praten over persoonlijke relaties en intimiteit kan lastig zijn, laat staan het in de praktijk brengen. Deze Exhale Week gaat over de diepe, vaak onuitgesproken thema’s rondom liefde, relaties, intimiteit en alles daartussenin . Om ons daarbij te helpen, hebben we samen met experts een gevarieerd programma samengesteld. Tijdens deze Exhale Week kun je kiezen uit een paneldiscussie en gesprekken met deskundigen op het gebied van psychologie en relaties, een acro-yoga workshop, een Drink & Draw kunstles over zelfportretten, Tarotlezingen en nog veel meer. En natuurlijk zijn er foodtrucks en drankjes! Programma & registreren Je kunt los deelnemen aan ieder onderdeel van de Exhale Week en je hebt hiervoor geen X-abonnement nodig . Het volledige programma is te bekijken op de website van Exhale . Bij sommige evenementen kun je zonder registratie binnenlopen en voor een aantal is een aanmelding vooral wel nodig. Wil je je aanmelden? Ook dat kan op de website ! Buiten de Exhale Weeks Buiten de vier Exhale Weeks omvat het programma tweewekelijkse evenementen en workshops. De Living Room is voor alle studenten van TU Delft elke dag geopend vanaf 12.00 uur en de Creative Studio is elke avond geopend vanaf 17.00 uur. Ook hiervoor is geen X-abonnement nodig. Over Exhale Exhale, a social living room powered by X, heeft een divers programma van workshops, evenementen en samenkomsten met als doel het faciliteren en ondersteunen van sociale verbinding, creativiteit en ontspanning. Vanaf 22 januari is Exhale zeven dagen per week geopend (ma-vr 12.00-22.30, za-zo 17.00-22.30) voor alle studenten van de TU Delft om gebruik te maken van de ruimte om te ontspannen, rond te hangen en op te laden.

Paving the road towards automated homogeneous catalyst design

In this paper, we discuss the history of using computational tools for designing transition-metal based homogeneous catalysts, current strategies and what challenges we see. A lot is said about the power of machine learning nowadays, but you can only do machine learning if you can also generate data reliably, reproducibly and at large scale. This is still a problem for this class of catalysts. We discuss the open-source Open Bidentate Ligand eXplorer (OBeLiX) Python package that we are developing for this purpose. Adarsh V. Kalikadien, Adrian Mirza, Aydin Najl Hossaini, Dr. Avadakkam Sreenithya, Prof. Dr. Evgeny A. Pidko Abstract In the past decade, computational tools have become integral to catalyst design. They continue to offer significant support to experimental organic synthesis and catalysis researchers aiming for optimal reaction outcomes. More recently, data-driven approaches utilizing machine learning have garnered considerable attention for their expansive capabilities. This Perspective provides an overview of diverse initiatives in the realm of computational catalyst design and introduces our automated tools tailored for high-throughput in silico exploration of the chemical space. While valuable insights are gained through methods for high-throughput in silico exploration and analysis of chemical space, their degree of automation and modularity are key. We argue that the integration of data-driven, automated and modular workflows is key to enhancing homogeneous catalyst design on an unprecedented scale, contributing to the advancement of catalysis research. Adarsh Kalikadien Read the publication

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Students Amos Yusuf, Mick Dam & Bas Brouwer winners of Mekel Prize 2024

Master students Amos Yusuf, from the ME faculty (Mick Dam, from the EEMCS faculty and graduate Bas Brouwer have won the Mekel Prize 2024 for the best extra scientific activity at TU Delft: the development of an initiative that brings master students into the classroom teaching sciences to the younger generations. The prize was ceremonially awarded by prof Tim van den Hagen on 13 November after the Van Hasselt Lecture at the Prinsenhof, Delft. They received a statue of Professor Jan Mekel and 1.500,- to spend on their project. Insights into climate change are being openly doubted. Funding for important educational efforts and research are being withdrawn. Short clips – so called “reels” – on Youtube and TikTok threaten to simplify complex political and social problems. AI fakes befuddle what is true and what is not. The voices of science that contribute to those discussion with modesty, careful argument and scepticism, are drowned in noise. This poses a threat for universities like TU Delft, who strive to increase student numbers, who benefit from diverse student populations and aim to pass on their knowledge and scientific virtues to the next generation. It is, therefore, alarming that student enrolments to Bachelor and Master Programs at TU Delft have declined in the past year. Students in front of the class The project is aimed to make the sciences more appealing to the next generation. They have identified the problem that students tend miss out on the opportunity of entering a higher education trajectory in the Beta sciences – because they have a wrong picture of such education. In their mind, they depict it as boring and dry. In his pilot lecture at the Stanislas VMBO in Delft, Amos Yusuf has successfully challenged this image. He shared his enthusiasm for the field of robotics and presented himself as a positive role model to the pupils. And in return the excitement of the high school students is palpable in the videos and pictures from the day. The spark of science fills their eyes. Bas Brouwer Mick Dam are the founders of NUVO – the platform that facilitates the engagement of Master Students in high school education in Delft Their efforts offer TU Delft Master Students a valuable learning moment: By sharing insights from their fields with pupils at high school in an educational setting, our students can find identify their own misunderstandings of their subject, learn to speak in front of non-scientific audiences and peak into education as a work field they themselves might not have considered. An extraordinary commitment According to the Mekel jury, the project scored well on all the criteria (risk mitigation, inclusiveness, transparency and societal relevance). However, it was the extraordinary commitment of Amos who was fully immersed during his Master Project and the efforts of Brouwer and Dam that brought together teaching and research which is integral to academic culture that made the project stand out. About the Mekel Prize The Mekel Prize will be awarded to the most socially responsible research project or extra-scientific activity (e.g. founding of an NGO or organization, an initiative or realization of an event or other impactful project) by an employee or group of employees of TU Delft – projects that showcase in an outstanding fashion that they have been committed from the beginning to relevant moral and societal values and have been aware of and tried to mitigate as much as possible in innovative ways the risks involved in their research. The award recognizes such efforts and wants to encourage the responsible development of science and technology at TU Delft in the future. For furthermore information About the project: https://www.de-nuvo.nl/video-robotica-pilot/ About the Mekel Prize: https://www.tudelft.nl/en/tpm/our-faculty/departments/values-technology-and-innovation/sections/ethics-philosophy-of-technology/mekel-prize

Veiligere en efficiëntere bloedvatbehandelingen door innovatieve kathetertechnologie

Wereldwijd worden jaarlijks meer dan 200 miljoen katheters gebruikt voor de behandeling van vaatziekten zoals hartaandoeningen en slagadervernauwing. Hoewel essentieel, brengt het gebruik van katheters risico’s met zich mee: wrijving tussen de katheter en de vaatwand kan complicaties veroorzaken. Een nieuwe technologie, ontwikkeld door Mostafa Atalla en zijn team, biedt een oplossing. Met één druk op de knop kan de wrijving van de katheter worden aangepast, van maximale grip naar volledige gladheid. Deze innovatie belooft niet alleen veiligere, maar ook efficiëntere endovasculaire procedures mogelijk te maken. De resultaten zijn gepubliceerd in het wetenschappelijk tijdschrift IEEE. Slimme katheter met instelbare wrijving Het nieuwe katheterprototype is uitgerust met geavanceerde technologie die de wrijving tussen de katheter en vaatwand nauwkeurig reguleert via ultrasone trillingen. Dit mechanisme zet via ultrasone trillingen de dunne vloeistoflaag onder druk waardoor de wrijving dynamisch kan worden aangepast: lage wrijving voor soepele navigatie door bloedvaten en hogere wrijving voor optimale stabiliteit tijdens een procedure. Tests tonen aan dat deze techniek de wrijving op harde oppervlakken met gemiddeld 60% vermindert en op zachte oppervlakken met 11%. Veelbelovende resultaten Bij experimenten op dierlijk aortaweefsel heeft het prototype zijn potentieel bewezen. Deze innovatie kan niet alleen bij vaatbehandelingen worden ingezet, maar mogelijk ook bij andere medische procedures, zoals interventies in de darmen. De onderzoekers zijn nu bezig de technologie verder te ontwikkelen en te testen op bredere toepassingen. Meer informatie Publicatie DOI: 10.1109/TMRB.2024.3464672 Toward Variable-Friction Catheters Using Ultrasonic Lubrication | IEEE Journals & Magazine | IEEE Xplore Mostafa Atalla: m.a.a.atalla@tudelft.nl/ Aimee Sakes: a.sakes@tudelft.nl Wil je een demonstratie bijwonen of in contact komen met een van de onderzoekers neem contact op met: Fien Bosman, persvoorlichter TU Delft Health: f.j.bosman@tudelft.nl/ 0624953733