The elephantarches bronze of Seleucos I Nikator

Un nouvel exemplaire de la monnaie en bronze de Séleucos Ier Nicatôr portant les types d’un homme assis/tête d’éléphant cornu (SC 25) révèle d’importants détails qui permettent l’identification de la figure du droit en tant que Dionysos dans son rôle de patron des éléphants de guerre indiens. Les éléphants sont un motif prédominant dans le monnayage de Séleucos Ier  : ils symbolisent la royauté nouvellement acquise et la victoire fondatrice de celle-ci. Le dieu est représenté sur une importante émission en argent de Suse, qui commémore la victoire remportée par Séleucos Ier à Ipsos. Les monnaies de bronze aux types Dionysos/tête d’éléphant cornu peuvent célébrer la même victoire ou, très probablement, celle remportée par le fondateur de la dynastie séleucide à Couropédion. Bien que Dionysos fut un dieu royal sous le règne de Séleucos Ier, il disparaît mystérieusement du monnayage de ses successeurs jusqu’au règne de Séleucos IV. Néanmoins, les portraits cornus de Séleucos II et Antiochos III pourraient assimiler ces rois à Dionysos.A new specimen of Seleucos Nikator’s bronze coin with the types seated figure/horned elephant head (SC 25) reveals details that identify the obverse type as Dionysos in his aspect as patron of Indian war elephants. Elephants are prominent on the coinage of Seleucos, where they serve as symbols of kingship and victory. Dionysos is represented on an important silver coinage of Susa that celebrates Seleucos’ victory at Ipsos. The Dionysos/horned elephant head bronzes may celebrate the same victory, or possibly that at Korupedion. Though a royal god under Seleucos, Dionysos mysteriously disappeared from the coinage of his successors until the reign of Seleucos IV. However the horned portraits of Seleucos II and Antiochos III may assimilate these kings to Dionysos.خلاصة – نموذج جديد لقطعة نقد برونزية لسيلوكوس الأول النبكاتوري، حيث يظهر بشكل رجل جالس/فيل ذو رأس مقرّن (SC 25)، تفاصيل مهمة تسمح بالتحقق من صورة ديونيزوس، على وجه العملة، بصفته سيّد لفيلة الحرب الهندية. إن الفيلة هي النموذج الأكثر ظهوراً في نقد سيلوكوس الأول، فهي ترمز الى الملكية المكتسبة حديثاً والإنتصار المؤسس لها. الإله يتمثل على إصدار فضّي مهم من سوسا والتي تخّلد النصر الذي حقّقه سيلوكوس الأول في إيبسوس. يمكن أن النقد البرونزي الذي يحمل نقش ديونيزوس برأس الفيل المقرّن ان يمجّد النصر ذاته او، وعلى الأرجح، الإنتصار الذي حققه مؤسس السلالة السلوقية في كوروبيديون. بالرغم من أن ديونيزوس كان الإله الملكي خلال عهد سيلوكوس الأول، الا أنه إختفى بغموض من مسكوكات خلفائه حتى عهد سيلوكوس الرابع. ولكن الصور المقرّنة لسيلوكوس الثاني وأنطيوكوس الثالث على نقودهم يمكن أن تمثّلهم بصفة ديونيزوس

Frequency response calibration of recess-mounted pressure transducers

A technique is described for measuring the frequency response of pressure transducers mounted inside a model, where a narrow pipette leads to an orifice at the surface. An acoustic driver is mounted to a small chamber which has an opening at the opposite end with an O-ring seal to place over the orifice. A 3.18 mm (1/8 inch) reference microphone is mounted to one side of the chamber. The acoustic driver receives an input of white noise, and the transducer and reference microphone outputs are compared to obtain the frequency response of the pressure transducer. Selected results are presented in the form of power spectra for both the transducer and the reference, as well as the amplitude variation and phase shift between the two signals as a function of frequency. The effect of pipette length and the use of this technique for identifying both blocked orifices and faulty transducers are described

A polymorph of tetra­ethyl­ammonium chloride

The structure of the title compound, C8H20N+·Cl−, is compared with a polymorph that was described earlier in the same space group. Differences in the conformations of the ethyl groups of the cation exist between the polymorphs. This study is given here in order to provide additional unit-cell data for use in qualitative identification of crystalline samples obtained in syntheses in which Et4N+·Cl− is either used or generated

Health professionals' knowledge of probiotics : an international survey

The objective of this study was to survey health professionals to investigate their knowledge of probiotics. An online survey was conducted to gather data on the knowledge of health professionals. The online survey was distributed via email and social media platforms using snowball sampling. A total of 1066 health professionals (859; 80.6% female) from 30 countries responded to the survey. Most of the respondents evaluated their knowledge of probiotics as medium (36.4%) or good (36.2%). Only 8.9% of the respondents rated it as excellent. No statistical difference in knowledge was found between male and female health professionals. Over 80% of pharmacists, allied health professionals, medical doctors and dentists, and other health professionals knew the correct definition of probiotics as “live microorganisms that, when administered in adequate amounts, confer a health benefit on the host”, whereas three quarters of registered nurses and midwives and less than two thirds of psychologists identified the correct definition. Statistically, more female than male health professionals knew the correct definition of probiotics. The most frequently recognized species of bacteria containing probiotic strains were Lactobacillus acidophilus (92%), Bifidobacterium bifidum (82%), and Lactobacillus rhamnosus (62%). The opinions on when it is best to take probiotics were different (χ2 = 28.375; p < 0.001), with 90.2% of respondents identifying that probiotics have beneficial effects if taken during antibiotic therapy, 83.5% for diarrhea, 70.6% for constipation, 63.3% before traveling abroad, and 60.4% for treating allergies. Almost 79% of health professionals involved in this study have advised their patients to use probiotics and 57.5% of the respondents wanted to learn more about probiotics. All things considered, health professionals have a medium level of knowledge of probiotics, which could be improved by the implementation of targeted learning programs. As probiotics have many beneficial effects in a wide range of health areas, health professionals need to adopt the use of probiotics in clinical practice

Bioink properties before, during and after 3D bioprinting

Bioprinting is a process based on additive manufacturing from materials containing living cells. These materials, often referred to as bioink, are based on cytocompatible hydrogel precursor formulations, which gel in a manner compatible with different bioprinting approaches. The bioink properties before, during and after gelation are essential for its printability, comprising such features as achievable structural resolution, shape fidelity and cell survival. However, it is the final properties of the matured bioprinted tissue construct that are crucial for the end application. During tissue formation these properties are influenced by the amount of cells present in the construct, their proliferation, migration and interaction with the material. A calibrated computational framework is able to predict the tissue development and maturation and to optimize the bioprinting input parameters such as the starting material, the initial cell loading and the construct geometry. In this contribution relevant bioink properties are reviewed and discussed on the example of most popular bioprinting approaches. The effect of cells on hydrogel processing and vice versa is highlighted. Furthermore, numerical approaches were reviewed and implemented for depicting the cellular mechanics within the hydrogel as well as for prediction of mechanical properties to achieve the desired hydrogel construct considering cell density, distribution and material-cell interaction

Relative Reactivity of the Metal-Amido versus Metal-Imido Bond in Linked Cp-Amido and Half-Sandwich Complexes of Vanadium

Treatment of (η5-C5H4C2H4NR)V(N-t-Bu)Me (R = Me, i-Pr) and CpV(N-p-Tol)(N-i-Pr2)Me (Cp = η5-C5H5) with B(C6F5)3 or [Ph3C][B(C6F5)4] results in formation of the corresponding cations, [(η5-C5H4C2H4NR)V(N-t-Bu)]+ and [CpV(N-p-Tol)(N-i-Pr2)]+. The latter could also be generated as its N,N-dimethylaniline adduct by treatment of the methyl complex with [PhNMe2H][BAr4] (Ar = Ph, C6F5). Instead, the analogous reaction with the linked Cp-amido precursor results in protonation of the imido-nitrogen atom. Sequential cyclometalation of the amide substituents gave cationic imine complexes [(η5-C5H4C2H4NCR'2)V(NH-t-Bu)]+ (R' = H, Me) and methane. Reaction of cationic [(η5-C5H4C2H4NR)V(N-t-Bu)]+ with olefins affords the corresponding olefin adducts, whereas treatment with 1 or 2 equiv of 2-butyne results in insertion of the alkyne into the vanadium-nitrogen single bond, affording the mono- and bis-insertion products [(η5-C5H4C2H4N(i-Pr)C2Me2)V(N-t-Bu)]+ and [(η5-C5H4C2H4N(i-Pr)C4Me4)V(N-t-Bu)]+. The same reaction with the half-sandwich compound [CpV(N-p-Tol)(N-i-Pr2)]+ results in a paramagnetic compound that, upon alcoholysis, affords sec-butylidene-p-tolylamine, suggesting an initial [2+2] cycloaddition reaction. The difference in reactivity between the V-N bond versus the V=N bond was further studied using computational methods. Results were compared to the isoelectronic titanium system CpTi(NH)(NH2). These studies indicate that the kinetic product in each system is derived from a [2+2] cycloaddition reaction. For titanium, this was found as the thermodynamic product as well, whereas the insertion reaction was found to be thermodynamically more favorable in the case of vanadium.

Schlieren Studies of Compressibility Effects on Dynamic Stall of Airfoils in Transient Pitching Motion

Compressibility effects on the flowfield of an airfoil executing rapid transient pitching motion from 0 - 60 degrees over a wide range of Mach numbers and pitching rates were studied using a stroboscopic schlieren flow visualization technique. The studies have led to the first direct experiments] documentation of multiple shocks on the airfoil upper surface flow for certain conditions. Also, at low Mach numbers, additional coherent vortical structures were found to be present along with the dynamic stall vortex, whereas at higher Mach numbers, the flow was dominated by a single vortex. The delineating Mach number for significant compressibility effects was 0.3 and the dynamic stall process was accelerated by increasing the Mach number above that value. Increasing the pitch rate monotonically delayed stall to angles of attack as large as 27 degrees.AFOSR-MIPR-87-0029 and 88-0010NAVAIRAR

Vanadium (β-(Dimethylamino)ethyl)cyclopentadienyl Complexes with Diphenylacetylene Ligands

Reduction of the V(III) (β-(dimethylamino)ethyl)cyclopentadienyl dichloride complex [η5:η1-C5H4(CH2)2NMe2]VCl2(PMe3) with 1 equiv of Na/Hg yielded the V(II) dimer {[η5:η1-C5H4(CH2)2NMe2]V(µ-Cl)}2 (2). This compound reacted with diphenylacetylene in THF to give the V(II) alkyne adduct [η5:η1-C5H4(CH2)2NMe2]VCl(η2-PhC≡CPh). Further reduction of 2 with Mg in the presence of diphenylacetylene resulted in oxidative coupling of two diphenylacetylene groups to yield the diamagnetic, formally V(V), bent metallacyclopentatriene complex [η5:η1-C5H4(CH2)2NMe2]V(C4Ph4).