Some applications of RF-gradients and excitation sculpting in NMR spectroscopy

AbstractRF-gradients produced utilizing RF-field inhomogenity of conventional receiver/transmitter coil of NMR-probe can be used to mimic the effects of B0-gradients. This is done by placing long inhomogenous pulse in between two 90° pulses of appropriate phases (z-rotation cluster). B0-gradient based excitation sculpting can be converted into RF-gradient version. Selective one-dimensional TOCSY and NOESY using RF-gradient based excitation sculpting are described. In addition, non-selective two-dimensional experiments, TOCSY and NOESY, with RF-gradient based coherence selection are presented. Excitation sculpting using BIRD or BIRDR as inversion element results in isotope filter. Pre-suppression of non-13C-bound protons using RF-gradient BIRD prior to HSQC enables recording of spectrum of comparable quality to B0-gradient selected HSQC. This is beneficial for spectrometers lacking B0-gradient capabilities. Excitation sculpting using BIRDR can be used efficiently as low-pass filter in HMBC experiment. Furthermore, simultaneous elimination of protons bound to 15N and 13C can be accomplished with BIRDR based method.Academic Dissertation to be presented with the assent of the Faculty of Science, University of Oulu, for public discussion in Raahensali (Auditorium L 10), Linnanmaa, on May 22nd, 1999, at 12 noon.Abstract RF-gradients produced utilizing RF-field inhomogenity of conventional receiver/transmitter coil of NMR-probe can be used to mimic the effects of B0-gradients. This is done by placing long inhomogenous pulse in between two 90° pulses of appropriate phases (z-rotation cluster). B0-gradient based excitation sculpting can be converted into RF-gradient version. Selective one-dimensional TOCSY and NOESY using RF-gradient based excitation sculpting are described. In addition, non-selective two-dimensional experiments, TOCSY and NOESY, with RF-gradient based coherence selection are presented. Excitation sculpting using BIRD or BIRDR as inversion element results in isotope filter. Pre-suppression of non-13C-bound protons using RF-gradient BIRD prior to HSQC enables recording of spectrum of comparable quality to B0-gradient selected HSQC. This is beneficial for spectrometers lacking B0-gradient capabilities. Excitation sculpting using BIRDR can be used efficiently as low-pass filter in HMBC experiment. Furthermore, simultaneous elimination of protons bound to 15N and 13C can be accomplished with BIRDR based method

Kilpailunrajoituksista immateriaalioikeuksien näkökulmasta

Siirretty Doriast

Synthesis and applications of secondary amine derivatives of (+)-dehydroabietylamine in chiral molecular recognition

(+)-Dehydroabietylamine (1a), the novel derivatives (2a-6a) and their NTf2 salts (1b-6b) were tested as chiral NMR solvating agents for the resolution of enantiomers of the model compound Mosher's acid (7) and its n-Bu4N salt (8). Best enantiomeric discrimination of 7 was obtained using bisdehydroabietyl-amino-N-1, N-2-ethane-1,2-diamine (6a), and of 8 using N-(dehydroabietyl)-2-(dehydroabietylamino) ethanaminium bis((trifluoromethyl)-sulfonyl)-amide (6b). For the maximal resolution of enantiomers of 8, 1.0 eq. of 6b were needed. However, 0.5 eq. of 6a sufficed for the maximal resolution of enantiomers of 7. Enantiomeric excess studies were successfully conducted using 6a and 6b. The capability of 6a and 6b to recognize the enantiomers of various a-substituted carboxylic acids and their n-Bu4N salts were examined. Best resolutions were observed for aliphatic and aromatic carboxylic acids bearing an electronegative alpha-substituent. Now the ee studies on such non-aromatic carboxylic acids are also feasible.Peer reviewe

A longitudinal study of interplay between student engagement and self-regulation

Abstract This study investigates the dynamic interplay between student engagement and self-regulated learning (SRL) in an online project management course. Using learning management system trace data combined with longitudinal self-reported SRL measures, we analysed data from 165 first-year business students through multi-channel sequencing and clustering algorithms. Results revealed three distinct patterns of learning behaviour with significant implications for intervention design: Low-regulating improvers (4.85%) who showed potential for growth with targeted support, Disengaged low regulators (44.85%) requiring comprehensive intervention in both engagement and self-regulation skills, and High-regulating improvers (50.30%) who demonstrated successful adaptation to online learning. Our innovative approach of analysing student progress individually rather than using fixed time points enabled more precise identification of support needs in asynchronous learning settings. The findings demonstrate that both engagement and self-regulation skills can develop over time with appropriate support, suggesting opportunities for adaptive intervention throughout the course. This research provides actionable insights for developing targeted support strategies, including early warning systems for at-risk students and personalized scaffolding approaches based on students' behavioural patterns. These findings advance learning analytics by providing a framework for real-time identification of student needs and evidence-based intervention design in online education. The results particularly emphasize the importance of continuous, pattern-based support for developing self-regulation skills in online environments.Abstract This study investigates the dynamic interplay between student engagement and self-regulated learning (SRL) in an online project management course. Using learning management system trace data combined with longitudinal self-reported SRL measures, we analysed data from 165 first-year business students through multi-channel sequencing and clustering algorithms. Results revealed three distinct patterns of learning behaviour with significant implications for intervention design: Low-regulating improvers (4.85%) who showed potential for growth with targeted support, Disengaged low regulators (44.85%) requiring comprehensive intervention in both engagement and self-regulation skills, and High-regulating improvers (50.30%) who demonstrated successful adaptation to online learning. Our innovative approach of analysing student progress individually rather than using fixed time points enabled more precise identification of support needs in asynchronous learning settings. The findings demonstrate that both engagement and self-regulation skills can develop over time with appropriate support, suggesting opportunities for adaptive intervention throughout the course. This research provides actionable insights for developing targeted support strategies, including early warning systems for at-risk students and personalized scaffolding approaches based on students' behavioural patterns. These findings advance learning analytics by providing a framework for real-time identification of student needs and evidence-based intervention design in online education. The results particularly emphasize the importance of continuous, pattern-based support for developing self-regulation skills in online environments

Hyötyä taseista : Ravinnetaseiden tulkinta ympäristön ja viljelyn hyödyksi

Hyötyä taseista -hankkeessa tuotettiin typen peltotaseiden jakaumat Suomen yleisimmille viljelykasveille yhdistämällä kaikki saatavilla oleva ja systemaattisesti kerätty ravinnetasetieto peltoviljelystä. Jakaumien perusteella viljelykasvit luokiteltiin neljään eri ryhmään: (I) säilörehunurmi, (II) kaura, ohra ja tärkkelysperuna, (III) kevätvehnä ja sokerijuurikas ja (IV) kevätrypsi, syysvehnä ja ruis. Kahden ensimmäisen ryhmän mediaanitaseet olivat samansuuruiset (kivennäismailla 13–14 kg/ha käytettäessä vain väkilannoitetyppeä), mutta säilörehunurmella typpitaseet olivat huomattavasti suuremmat jakauman yläpäässä. Kasviryhmässä III mediaanitase oli vastaavasti 32 kg/ha ja ryhmässä IV kaikkein korkein, 56 kg/ha. Typpitaseet olivat lisäksi em. kasviryhmissä eloperäisillä mailla pienempiä kuin kivennäismailla. Kotieläinlantaa käytettäessä typpitaseet laskettuna liukoisen typen mukaan olivat hieman suurempia kasviryhmässä II kun taas ryhmissä III ja IV eroa ei ollut tai tase oli pienempi (säilörehunurmi). Kasviryhmien sisällä typpitaseen suuruuteen vaikutti eniten typpilannoituksen määrä. Matalimmat taseet saavutettiin, kun satotaso oli korkea ilman että oli käytetty ympäristökorvauksen enimmäislannoitusmääriä. Korkeita typpitaseita sen sijaan esiintyi, kun satotaso oli jäänyt odotettua pienemmäksi huolimatta typpilannoituksesta. Tasejakaumiin liitettiin ympäristöinformaatio potentiaalisesta vesistökuormituksesta, jota arvioitiin koeaineistojen ja mallintamisen avulla. Kasviryhmissä I ja II noin neljännes liukoisen typen taseista oli niin korkeita (ylittävät tason 60 ja 25 kg/ha), että niistä voi aiheutua keskimääräistä selvästi korkeampi typen huuhtoutumisriski. Kasviryhmässä III puolet typpitaseista ylitti riskirajan ja ryhmässä IV yli puolet. Typpitaseita tarkasteltiin myös laskemalla op-timaalisen typpilannoituksen määrää erilaisilla hintasuhteilla. Tulosten perusteella nitraattiasetus ei rajoita taloudellisesti optimaalista typpilannoitusta kevätviljoilla, mutta rajoittaa typpilannoitusta säilörehunurmen kohdalla. Ympäristökorvauksen enimmäislannoitusmäärät johtavat kevätviljoilla typpitaseisiin (16–45 kg/ha kivennäismailla), jotka ovat keskimääräistä korkeampia verrattuna em. peltolohkojen jakaumiin, mutta eivät johda peltolohkoilla havaittuihin suurimpiin typpitaseisiin. Verrattuna rajoittamattomaan taloudelliseen optimointiin, ympäristökorvaukseen sitoutuneilla maatiloilla kasvintuotannosta saatava vuotuinen katetuotto vähenee usein vain alle 10 €/ha vil-jeltäessä viljaa kivennäismailla, kun taas säilörehun tuotannossa vastaava vähenemä on lähes 50 €/ha. Tuloksia havainnollistettiin esittämällä alustavia kriteerejä typpitaseiden arviointiin ja joillekin kasveille ehdotettiin myös liukoisen typen taseiden viitearvoja mahdollista ravinnetaseohjausta varten. Ravinnetaseisiin perustuvan ohjauksen vahvuudeksi tunnistettiin satotason huomiointi, mikä voisi kannustaa peltojen perusparannuksiin.201

Search for Microscopic Black Hole Signatures at the Large Hadron Collider

Peer reviewe

MAGIC polymer gel for dosimetric verification in boron neutron capture therapy

"Radiation-sensitive polymer gels are among the most promising three-dimensional dose verification tools developed to date. We tested the normoxic polymer gel dosimeter known by the acronym MAGIC (methacrylic and ascorbic acid in gelatin initiated by copper) to evaluate its use in boron neutron capture therapy (BNCT) dosimetry. We irradiated a large cylindrical gel phantom (diameter: 10 cm; length: 20 cm) in the epithermal neutron beam of the Finnish BNCT facility at the FiR 1 nuclear reactor. Neutron irradiation was simulated with a Monte Carlo radiation transport code MCNP. To compare dose-response, gel samples from the same production batch were also irradiated with 6 MV photons from a medical linear accelerator. Irradiated gel phantoms then underwent magnetic resonance imaging to determine their R2 relaxation rate maps. The measured and normalized dose distribution in the epithermal neutron beam was compared with the dose distribution calculated by computer simulation. The results support the feasibility of using MAGIC gel in BNCT dosimetry.""Radiation-sensitive polymer gels are among the most promising three-dimensional dose verification tools developed to date. We tested the normoxic polymer gel dosimeter known by the acronym MAGIC (methacrylic and ascorbic acid in gelatin initiated by copper) to evaluate its use in boron neutron capture therapy (BNCT) dosimetry. We irradiated a large cylindrical gel phantom (diameter: 10 cm; length: 20 cm) in the epithermal neutron beam of the Finnish BNCT facility at the FiR 1 nuclear reactor. Neutron irradiation was simulated with a Monte Carlo radiation transport code MCNP. To compare dose-response, gel samples from the same production batch were also irradiated with 6 MV photons from a medical linear accelerator. Irradiated gel phantoms then underwent magnetic resonance imaging to determine their R2 relaxation rate maps. The measured and normalized dose distribution in the epithermal neutron beam was compared with the dose distribution calculated by computer simulation. The results support the feasibility of using MAGIC gel in BNCT dosimetry.""Radiation-sensitive polymer gels are among the most promising three-dimensional dose verification tools developed to date. We tested the normoxic polymer gel dosimeter known by the acronym MAGIC (methacrylic and ascorbic acid in gelatin initiated by copper) to evaluate its use in boron neutron capture therapy (BNCT) dosimetry. We irradiated a large cylindrical gel phantom (diameter: 10 cm; length: 20 cm) in the epithermal neutron beam of the Finnish BNCT facility at the FiR 1 nuclear reactor. Neutron irradiation was simulated with a Monte Carlo radiation transport code MCNP. To compare dose-response, gel samples from the same production batch were also irradiated with 6 MV photons from a medical linear accelerator. Irradiated gel phantoms then underwent magnetic resonance imaging to determine their R2 relaxation rate maps. The measured and normalized dose distribution in the epithermal neutron beam was compared with the dose distribution calculated by computer simulation. The results support the feasibility of using MAGIC gel in BNCT dosimetry."Peer reviewe

CMS The Computing Project : Technical Design Report

Peer reviewe