Hindwings of insects as concept generator for hingeless foldable shading systems

Hingeless shading systems inspired by nature are increasingly the focus of architectural research. In contrast to traditional systems, these compliant mechanisms can reduce the amount of maintenance-intensive parts and can easily be adapted to irregular, doubly curved, facade geometries. Previous mechanisms rely merely on the reversible material deformation of composite structures with almost homogeneous material properties. This leads to large actuation forces and an inherent conflict between the requirements of movement and the capacity to carry external loads. To enhance the performance of such systems, current research is directed at natural mechanisms with concentrated compliance and distinct hinge zones with high load-bearing capacity. Here, we provide insights into our biological findings and the development of a deployable structure inspired by the Flexagon model of hindwings of insects in general and the hierarchical structure of the wing cuticle of the shield bug (Graphosoma lineatum). By using technical fibre-reinforced plastics in combination with an elastomer foil, natural principles have been partially transferred into a multi-layered structure with locally adapted stiffness. Initial small prototypes have been produced in a vacuum-assisted hot press and sustain this functionality. Initial theoretical studies on test surfaces outline the advantages of these bio-inspired structures as deployable external shading systems for doubly curved facades.

Current management of premenstrual syndrome and premenstrual dysphoric disorder

About 5% of women of reproductive age experience affective or physical premenstrual symptoms that markedly influence work, social activities, or relationships. Prospective charting of symptoms for at least two menstrual cycles is required to facilitate an accurate diagnosis of premenstrual syndrome or premenstrual dysphoric disorder. The optimal treatment plan begins with lifestyle modifications, followed by pharmacotherapy. Evidence from numerous controlled trials has clearly demonstrated that low-dose serotonin reuptake inhibitors, using intermittent or continuous administration, have excellent efficacy with minimal side effects. Modification of the menstrual cycle should be considered only after all other treatment options have failed.

Diagnosis and treatment of premenstrual dysphoric disorder: an update

Premenstrual dysphoric disorder (PMDD) appears in the appendix of the DSM-IV under the heading 'depressive disorder not otherwise specified'. Yet, recently, a group of experts reached a consensus that PMDD is a distinct clinical entity with characteristic symptoms of irritability, anger, internal tension, dysphoria, and mood lability. PMDD is the more severe form of premenstrual symptomatology, whereas premenstrual syndrome (PMS) is milder and more prevalent and both must be differentiated from premenstrual magnification/exacerbation of an underlying major psychiatric disorder or a medical condition. Accurate assessment and diagnosis of significant premenstrual symptomatology is paramount and can be influenced by subjective perception, retrospective versus prospective reporting, and cultural context. The serotonergic system, which is in a close reciprocal relationship with the gonadal hormones, has been identified as the most plausible target for intervention. Results from randomized placebo-controlled trials in women with PMDD have clearly demonstrated that serotonin reuptake inhibitors (SSRIs), with daily or intermittent dosing, have excellent efficacy and minimal adverse effects and should be considered first-line treatment. Luteal phase only SSRI administration may offer an attractive treatment option for a disorder that is itself intermittent. Hormonal interventions, in particular the suppression of ovulation will eliminate premenstrual symptomatology; however, the benefits-risk ratio of these approaches should be carefully evaluated with the patient.

Genetic variation at the porcine MYF-5 gene locus. Lack Of association with meat production traits

The number of muscle fibers at birth appears to determine the maximal lean meat growth capacity in pigs and in cattle. Development of muscle fibers is regulated by the MyoD gene family consisting of MyoD1, myf-5, myf-6, and myogenin. Myf-5 is expressed in proliferating myoblasts. Here we report the genomic sequence of the porcine myf-5 gene with three microsatellites and two RFLPs located close to the coding sequences. Two of the microsatellites are located in the promoter region. The allelic distribution differs between breeds and selection lines. In two GY selection lines, 1216 pigs of two-generation families were genotyped for the HinfI RFLP, which was segregating in the GY breed. The other polymorphic loci are physically linked to this RFLP locus, and therefore the results can be extrapolated to these loci. Statistical analysis revealed no association with birth weight, growth rate, weight at slaughter age, carcass meat weight, and backfat thickness. Thus, in this study myf-5 did not explain genetic variation in meat (muscle) development in pigs.

Determination of the absolute configuration of the active amlodipine enantiomer as (-)-S: a correction

The active (-) enantiomer of amlodipine was originally reported to have R configuration. This does not concur with other 1,4-dihydropyridines with known absolute configuration. This configuration has now been determined by X-ray structural analysis using (1S)-camphanic acid and (S)-2-methoxy-2-phenylethanol as chiral probes. Both determinations gave the S configuration for the amlodipine (-) enantiomer with the greater Ca-antagonistic activity.

[The Relative Configuration of Acetogenins Isolated from Annona squamosa: Annonin I (Squamocin) and Annonin VI]

Annonin I ( 1) and anonin VI ( 9) were isolated from the seeds of ANNONA SQUAMOSA L. (Annonaceae). The constitution of 1 is identical with that of squamocin, isolated by Fujimoto et al. (8). The relative configuration of 1 was elucidated by X-ray diffraction analysis of a derivative. The constitution and relative configuration of 9 was established by (13)C- and (1)H-NMR spectroscopy using data of derivatives.

Synthesis, pharmacological effects, and conformation of 4,4-disubstituted 1,4-dihydropyridines

4,4-Disubstituted 1,4-dihydropyridines are synthesized by intramolecular addition of sulfinyl carbanions to pyridines. These disubstituted derivatives show a loss of Ca antagonistic potency of up to three powers of 10 both in vitro on aortic rings and in vivo on anaesthetized dogs as compared to examples that are monosubstituted at the 4-position of the DHP ring. As the X-ray structure shows, the 4-aryl substituent is present not in the accustomed axial conformation, but in an equatorial one. This dramatic change in conformation could be the reason for the major loss of activity and would indicate the need for axial conformation of the aryl residue in pharmacologically active 1,4-dihydropyridines. The change in conformation was also confirmed by quantum chemical calculations (AM1).