Relatively computably enumerable reals

A real X is defined to be relatively c.e. if there is a real Y such that X is c.e.(Y) and Y does not compute X. A real X is relatively simple and above if there is a real Y <_T X such that X is c.e.(Y) and there is no infinite subset Z of the complement of X such that Z is c.e.(Y). We prove that every nonempty Pi^0_1 class contains a member which is not relatively c.e. and that every 1-generic real is relatively simple and above.Comment: 5 pages. Significant changes from earlier versio

Physical and chemical quenching rates and their influence on stereoselective photooxygenation of oxazolidinone-functionalized enecarbamates

Physical and chemical quenching rate constants were measured for the reaction of singlet oxygen with oxazolidinone-functionalized enecarbamates to investigate the role of vibrational deactivation in product stereoselectivity

Magnetic and spin effects in the photoinitiation of polymerization

Application of a moderate external magnetic field increases the efficiency of triplet photoinitiators of polymerization. The reasons for this observation are briefly outlined. Such well-documented magnetic and spin effects as the magnetic isotope effect (MIE) and chemically induced dynamic nuclear and electron polarization (CIDNP and CIDEP) have been observed under the photolysis of photoinitiators. CIDEP results are emphasized. The study of CIDEP under the photolysis of initiators allows the detection and identification of free radicals of initiators and the spin multiplicity of the reacting photoinitiator (triplet or singlet). The transfer of the spin polarization of the initiator free radical to monomers is a promising technique for following radical reaction pathways. The results of a CIDEP study of the sensitized decomposition of phosphine oxide photoinitiators are presented

Vibrational deactivation of singlet oxygen: does it play a role in stereoselectivity during photooxygenation?

Oxazolidinone-substituted enecarbamates offer a system to explore vibrational quenching and the strategic placement of CH bonds as a method for manipulating the stereoselectivity of photoreactions

On the Necessity of a Geriatric Oral Health Care Transition Model: Towards an Inclusive and Resource-Oriented Transition Process

People in need of care also require support within the framework of structured dental care in their different life situations. Nowadays, deteriorations in oral health tend to be noticed by chance, usually when complaints or pain are present. Information on dental care is also lost when life situations change. An older person may rely on family members having oral health skills. This competence is often not available, and a lot of oral health is lost. When someone, e.g., a dentist, physician, caregiver, or family member notices a dental care gap, a structured transition to ensure oral health should be established. The dental gap can be detected by, e.g., the occurrence of bad breath in a conversation with the relatives, as well as in the absence of previously regular sessions with the dental hygienist. The aim of the article is to present a model for a structured geriatric oral health care transition. Due to non-existing literature on this topic, a literature review was not possible. Therefore, a geriatric oral health care transition model (GOHCT) on the basis of the experiences and opinions of an expert panel was developed. The GOHCT model on the one hand creates the political, economic, and legal conditions for a transition process as a basis in a population-relevant approach within the framework of a transition arena with the representatives of various organizations. On the other hand, the tasks in the patient-centered approach of the transition stakeholders, e.g., patient, dentist, caregivers and relatives, and the transition manager in the transition process and the subsequent quality assurance are shown

Stereoselective E/Z photoisomerization of oxazolidinone functionalized enecarbamates: direct and triplet sensitized irradiation

Oxazolidinone-functionalized enecarbamates undergo diastereoselective E/Z photoisomerization upon direct and triplet sensitized irradiations with chiral/achiral sensitizers, showing that the enhanced product diastereoselectivity depends on the solvent and temperature

Controlled diastereoselectivity at the alkene-geometry through selective encapsulation: E-Z photoisomerization of oxazolidinone-functionalized enecarbamates within hydrophobic nano-cavities

Photoisomerization of encapsulated Z-enecarbamates within the hydrophobic chiral cavities of γ-CD showed higher diastereoselectivities in the photoproducts than those obtained in solution. The selective encapsulation of the enecarbamates and the following isomerization process are both diastereoselectively controlled by γ-CD

Molecular beacons with intrinsically fluorescent nucleotides

We report the design, synthesis and characterization of a novel molecular beacon (MB-FB) which uses the fluorescent bases (FB) 2-aminopurine (AP) and pyrrolo-dC (P-dC) as fluorophores. Because the quantum yield of these FB depend on hybridization with complementary target, the fluorescent properties of MB-FB were tuned by placing the FB site specifically within the MB such that hybridization with complementary sequence switches from single strand to double strand for AP and vice versa for P-dC. The MB-FB produces a ratiometric fluorescence increase (the fluorescence emission of P-dC over that of AP in the presence and absence of complementary sequence) of 8.5 when excited at 310 nm, the maximum absorption of AP. This ratiometric fluorescence is increased to 14 by further optimizing excitation (325 nm). The fluorescence lifetime is also affected by the addition of target, producing a change in the long-lived component from 6.5 to 8.7 ns (Exc. 310 nm, Em. 450 nm). Thermal denaturation profiles monitored at 450 nm (P-dC emission) show a cooperative denaturation of the MB-FB with a melting temperature of 53°C. The thermal denaturation profile of MB-FB hybridized with its target shows a marked fluorescence reduction at 53°C, consistent with a transition from double stranded helix to random coil DNA

Student Perceptions of Age and Ageing-An Evaluation of Swiss Dental Students Receiving Education in Gerodontology

Society is ageing and the higher number of senior citizens in the total population is a challenge for society and often perceived as a burden. Negative images of old age can lead to ageism and poorer healthcare for older people. The younger generation will have to master these demographic challenges. Therefore, their attitude towards and their perception of the older generation has to be monitored. The aim of this study is to present the images of ageing held by dental students who received education in gerodontology and to assess possible changes between different generations of students over time and separated by gender. An annual, anonymous questionnaire survey was conducted among dental students at the end of the 10th semester each year between 2008 and 2021. The questionnaire surveyed personal attitudes towards ageing, the assessment of seniors, and personal experience with seniors (images of ageing, "Aging Semantic Differential"). In addition to confirming Friedan's phenomenon regarding the assessment of age limits, the present study was able to demonstrate a positive image of ageing in dental students, which has remained almost constant over the years. An education in gerodontology might positively influence student perceptions of age and aging