Environmental effects on magnetic fluorescent powder development of fingermarks on bird of prey feathers

A comparison study of the effects of environmental conditions on the development of latent fingermarks on raptor feathers using green magnetic fluorescent powder was undertaken using both sebaceous loaded and natural fingermark deposits. Sparrowhawk feathers were stored in indoor conditions for 60 days (Study 1), and buzzard feathers were left exposed to two different environmental conditions (hidden and visible) for 21 days (Study 2), with developments made at regular ageing periods. In Study 1, latent fingermarks were successfully developed (Grade 1–4) on the indoor feathers up to 60 days after deposition – 98.6% of the loaded deposits and 85.3% for natural deposits. Under outdoor conditions in Study 2, both loaded and natural deposits were affected by environmental exposure. Latent fingermarks were successfully developed up to 14 days after deposition on the outdoor feathers, with some occasional recovery after 21 days. The visible feathers recorded 34.7% (loaded) and 16.4% (natural) successful developments (Grade 1–4), whereas the hidden feathers recorded 46.7% (loaded) and 22.2% (natural) successful developments, suggesting that protection from the environment helps to preserve latent fingermarks on the surface of a feather. Environmental exposure accelerated the deterioration of ridge detail and the number of successful developments

Dar fuq ir-ramel

Ġabra ta’ poeżiji u proża li tinkludi: Taħt l-anestetiku ta’ Lino Farrugia Bonnici – Dar fuq ir-ramel ta’ Charles D. Clews.N/

Evolutionary signatures in complex ejecta and their driven shocks

We examine interplanetary signatures of ejecta-ejecta interactions. To this end, two time intervals of inner-heliospheric (≤1AU) observations separated by 2 solar cycles are chosen where ejecta/magnetic clouds are in the process of interacting to form complex ejecta. At the Sun, both intervals are characterized by many coronal mass ejections (CMEs) and flares. In each case, a complement of observations from various instruments on two spacecraft are examined in order to bring out the in-situ signatures of ejecta-ejecta interactions and their relation to solar observations. In the first interval (April 1979), data are shown from Helios-2 and ISEE-3, separated by ~0.33AU in radial distance and 28° in heliographic longitude. In the second interval (March-April 2001), data from the SOHO and Wind probes are combined, relating effects at the Sun and their manifestations at 1AU on one of Wind's distant prograde orbits. At ~0.67AU, Helios-2 observes two individual ejecta which have merged by the time they are observed at 1AU by ISEE-3. In March 2001, two distinct Halo CMEs (H-CMEs) are observed on SOHO on 28-29 March approaching each other with a relative speed of 500kms<sup>-1</sup> within 30 solar radii. In order to isolate signatures of ejecta-ejecta interactions, the two event intervals are compared with expectations for pristine (isolated) ejecta near the last solar minimum, extensive observations on which were given by Berdichevsky et al. (2002). The observations from these two event sequences are then intercompared. In both event sequences, coalescence/merging was accompanied by the following signatures: heating of the plasma, acceleration of the leading ejecta and deceleration of the trailing ejecta, compressed field and plasma in the leading ejecta, disappearance of shocks and the strengthening of shocks driven by the accelerated ejecta. A search for reconnection signatures at the interface between the two ejecta in the March 2001 event was inconclusive because the measured changes in the plasma velocity tangential to the interface (Δν<sub>t</sub>) were not correlated with Δ(<i>B<sub>t</sub></i> /ρ). This was possibly due to lack of sufficient magnetic shear across the interface. The ejecta mergers altered interplanetary parameters considerably, leading to contrasting geoeffects despite broadly similar solar activity. The complex ejecta on 31 March 2001 caused a double-dip ring current enhancement, resulting in two great storms (<i>D<sub>st</sub></i>, corrected for the effect of magnetopause currents, <-450nT), while the merger on 5 April 1979 produced only a corrected <i>D<sub>st</sub></i> of ~-100nT, mainly due to effects of magnetopause currents

Bioactive flavanones from Luma chequen

A bioassay-guided chemical study of a methanolic extract of fresh leaves of Luma chequen led to the isolation of lumaflavanones A (1), B (2) and C (3) whose structures are proposed on the basis of NMR spectroscopic data. The structure of lumaflavanone A was confirmed by X-ray analysis. Antifeedant (Spodoptera littoralis), brine shrimp (Artemia salina) and fungistatic (Botrytis cinerea) bioassays showed that while 3 was the most active in the first two assays the mixture of 1 and 2 was more effective as a fungistatic

A monoclinic polymorph of N,N′-bis­(2,6-diisopropyl­phen­yl)formamidine

A new polymorph of N,N′-bis­(2,6-diisopropyl­phen­yl)formamidine, C25H36N2, is reported, which is different from the previously reported ortho­rhom­bic structure. The mol­ecule crystallizes in the E–anti configuration, with tautomeric disorder of the N-bonded H atoms and no clear distinction between imine and amine functionalities. The mol­ecules form hydrogen-bonded dimers with inter­molecular N⋯N distances shorter than those in the ortho­rhom­bic polymorph

Kilohertz QPOs in Neutron Star Binaries modeled as Keplerian Oscillations in a Rotating Frame of Reference

Since the discovery of kHz quasi-periodic oscillations (QPO) in neutron star binaries, the difference between peak frequencies of two modes in the upper part of the spectrum, i.e. Delta (omega)=omega_h-omega_K has been studied extensively. The idea that the difference Delta(omega) is constant and (as a beat frequency) is related to the rotational frequency of the neutron star has been tested previously. The observed decrease of Delta(omega) when omega_h and omega_k increase has weakened the beat frequency interpretation. We put forward a different paradigm: a Keplerian oscillator under the influence of the Coriolis force. For such an oscillator, omega_h and the assumed Keplerian frequency omega_k hold an upper hybrid frequency relation: omega^2_h-omega^2_K=4*Omega^2, where Omega is the rotational frequency of the star's magnetosphere near the equatorial plane. For three sources (Sco X-1, 4U 1608-52 and 4U 1702-429), we demonstrate that the solid body rotation Omega=Omega_0=const. is a good first order approximation. Within the second order approximation, the slow variation of Omega as a function of omega_K reveals the structure of the magnetospheric differential rotation. For Sco X-1, the QPO have frequencies approximately 45 and 90 Hz which we interpret as the 1st and 2nd harmonics of the lower branch of the Keplerian oscillations for the rotator with vector Omega not aligned with the normal of the disk: omega_L/2 pi=(Omega/pi)(omega_K/omega_h)sin(delta) where delta is the angle between vector Omega and the vector normal to the disk.Comment: 13 pages, 3 figures, accepted for publications in ApJ Letter

Ethyl 4-hydroxy­methyl-2-methyl­pyridine-5-carboxyl­ate

The title compound, C10H13NO3, was obtained as a by-product of the aldolization reaction of furo[3,4-c]pyridin-3(1H)-one with thio­phene-2-carboxaldehyde. The substituents on the pyridine ring are nearly coplanar, with an 8.1 (2)° rotation of the hydroxmethyl group from this plane. The mol­ecules assemble in the crystal structure as chains via O—H⋯N hydrogen bonding between the pyridine N atom and a neighbouring hydroxy­methyl OH group

(1-Bromo­naphthalen-2-yl)acetonitrile

The title compound, C12H8BrN, was prepared as a starting material for a Suzuki cross-coupling reaction with a pinacol ester. The torsion angle about the ring–methylene C—C bond is 30.7 (3)°, such that the N atom is displaced by 1.174 (4) Å from the plane of the naphthalene ring system

2-[(1-{[3-(dimethylazaniumyl)propyl]methylamino}ethylidene)azaniumyl]­nona­hydro-closo-deca­borate dimethyl sulfoxide disolvate

The title compound, 2-B10H9NH=C(CH3)N(CH3)CH2CH2CH2N(CH3)2H·2C2H6OS or C8H29B10N3·2C2H6OS, is zwitterionic with the negative charge localized on the deca­borate cage and the positive charge on the terminal ammonium group. Two mol­ecules of dimethyl sulfoxide (DMSO) and one mol­ecule of the title compound constitute the asymmetric unit. One DMSO mol­ecule is disordered [ratio 0.739 (3):0.261 (3)]. The bonds and angles within the deca­borate cage are within the normal ranges. The amidine fragment of the ligand, which is expected to be planar, is significantly distorted from planarity as exemplified by four torsion angles [B—N—C—C = 8.4 (3), H—N—C—N = 5(2), N—C—N—C = 7.3 (3) and C—C—N—C = 14.8 (3)°] found within this portion of the mol­ecule. The crystal packing consists of head-to-tail-arranged dimers of the title mol­ecule held together by four mol­ecules of DMSO which are attached via strong N—H⋯O and weak C—H⋯O hydrogen bonds