Slow magnetic relaxation in a ferromagnetic CuII chain complex, induced by a phonon bottleneck effect.

The first slow magnetic relaxation in a ferromagnetic Cu(II) chain compound, Cu(dipic)(OH2)2 (dipicH2 = pyridine-2,6-dicarboxylic acid), induced by a phonon bottleneck effect under a magnetic field of 0.6 T, with a relaxation time of 2.2 s at 2.8 K, was observed.

Confocal Raman microscopic evidence for cyclic water Pentamer, at high temperatures in a supramolecular host of [Cu(cyclam)(N3)2]·4H2O.

Here, we report the existence of a pentameric water cluster in the host framework of [Cu(cyclam)(N3)2]·4H2O, that is stable upto 167 °C, well above the boiling point of water. The pentameric cluster structure embedded in the host framework is evident from the single crystal studies. The high thermal stability is confirmed by TGA and temperature dependent confocal Raman microscopic studies, where loss of water bands is well captured between 167 and 170 °C, besides its existence through SCXRD studies. To the best of our knowledge, this is the first report where temperature dependent confocal Raman microscopic investigation is used to study the stability of water in crystal environment. The study promises that temperature dependent confocal Raman microscopy can be an efficient tool to investigate the existence and stability of small water clusters, precisely in restricted environments.

Emission analysis of Tb3+ -and Sm3+ -ion-doped (Li2 O/Na2 O/K2 O) and (Li2 O + Na2 O/Li2 O + K2 O/K2 O + Na2 O)-modified borosilicate glasses.

Four series of borosilicate glasses modified by alkali oxides and doped with Tb3+ and Sm3+ ions were prepared using the conventional melt quenching technique, with the chemical composition 74.5B2 O3 + 10SiO2 + 5MgO + R + 0.5(Tb2 O3 /Sm2 O3 ) [where R = 10(Li2 O /Na2 O/K2 O) for series A and C, and R = 5(Li2 O + Na2 O/Li2 O + K2 O/K2 O + Na2 O) for series B and D]. The X-ray diffraction (XRD) patterns of all the prepared glasses indicate their amorphous nature. The spectroscopic properties of the prepared glasses were studied by optical absorption analysis, photoluminescence excitation (PLE) and photoluminescence (PL) analysis. A green emission corresponding to the 5 D4 → 7 F5 (543 nm) transition of the Tb3+ ions was registered under excitation at 379 nm for series A and B glasses. The emission spectra of the Sm3+ ions with the series C and D glasses showed strong reddish-orange emission at 600 nm (4 G5/2 →6 H7/2 ) with an excitation wavelength λexci = 404 nm (6 H5/2 →4 F7/2 ). Furthermore, the change in the luminescence intensity with the addition of an alkali oxide and combinations of these alkali oxides to borosilicate glasses doped with Tb3+ and Sm3+ ions was studied to optimize the potential alkali-oxide-modified borosilicate glass.

Ligand directed structural diversity and magnetism in copper(ii)-azido assemblies with isomeric aminopyridines: synthesis, structure, magnetism and theoretical studies.

Four new copper complexes, viz. [{Cu(2-aminopyridine)(N3)2(H2O)}2]n (1), [Cu3(3-aminopyridine)2(N3)6]n (2), [{Cu(3-aminopyridine)(N3)2}2]n (3), and [Cu(4-aminopyridine)2(N3)2]n (4), have been synthesized with isomeric aminopyridines, viz. 2-aminopyridine (2-ap), 3-aminopyridine (3-ap), and 4-aminopyridine (4-ap), to probe the role of ligand and reactant molar ratios in directing the polynuclear assemblage and the associated magnetic properties. Ligand geometry is quite influential as can be seen through the versatile structures formed, viz. a hydrogen bonded layer of µ-1,1 azide bridged Cu dimers in 1; a network of two different types of dimers (Cu1-Cu2 & Cu3-Cu3') involving µ-1,1; µ-1,3; µ-1,1,3; & µ-1,1,3,3 azide bridges in 2; a ladder structure in which µ-1,1 azide bridges form the rungs and µ-1,3 azide bridges form the rails of the ladder in 3; and a 1-D polymer chain involving µ-1,1 azide bridges in 4. Consistent with the bridge geometry, compounds 1 & 2 display ferromagnetic interactions, while 3 & 4 display antiferromagnetic interactions. The rather unexpected antiferromagnetic interactions in 3, in spite of µ-1,1 azide bridged rungs may be due to the crossover near the bridge angle. The ferromagnetic interactions in 1 and 2 are supported by DFT calculations.

Luminescence analysis of SrGa2 Si2 O8 : RE3+ (RE = Dy, Tm) phosphors.

This article reports on the luminescence properties of rare earth (Dy3+ and Tm3+ )ions doped SrGa2 Si2 O8 phosphor were studied. SrGa2 Si2 O8 phosphors weresynthesizedby employing solid state reaction method.From the measured X-ray diffraction (XRD) pattern of the samplemonoclinic phase structure has been observed. Thermoluminescenceand Mechanoluminescence properties of the γ-ray irradiated samples have been studied. Photoluminescence spectra of Dy3+ activated SrGa2 Si2 O8 phosphor has been measured with an excitation wavelength at 348 nm,and it shows two emission bands at 483 and 574 nm due to 4 F9/2  â†’ 6 H15/2 and 4 F9/2  â†’ 6 H13/2 transitions respectively. Whereas the photoluminescence spectra of Tm3+ activated SrGa2 Si2 O8 phosphor has been measured with an excitation wavelength at 359 nm and it exhibits two emission bands at 454 and 472 nm due to 1 D2  â†’ 3 F4 and1 G4  â†’ 3 H6 transitions respectively. In thermoluminescence study, γ-irradiatedthermoluminescence glow curve of SrGa2 Si2 O8 :Dy3+ phosphor shows two well defined peaks at 293 °C (peak1)and 170 °C (peak2) whereas thermoluminescence glow curve of SrGa2 Si2 O8 :Tm3+ phosphor shows peaks at 292 °C (peak1) and 184 °C (peak2) indicating that two sets of traps are being activated within the particular temperature range and the trapping parameters associated with the prominent glow peaks of SrGa2 Si2 O8 :Dy3+ and SrGa2 Si2 O8 :Tm3+ are calculated using Chen's peak shape and initial rise method.From the Mechanoluminescence study, only one glow peak has been observed. Copyright © 2016 John Wiley & Sons, Ltd.

Partial Sternal Resections in Primary and Metastatic Tumors with Nonrigid Reconstruction of Chest Wall.

Primary sternal tumors are rare and are often metastatic from neoplasms of lung, breast, thyroid, and kidney. A radical resection is indicated for their management. In recent years many rigid reconstructions are described to prevent pulmonary complications and for protection of intra -thoracic organs. It is known that chest wall is a stable yet flexible structure and hence the optimal functional outcome in spite of rigid reconstructions remains an ongoing challenge. We hypothesized that partial sternal resections does not need a rigid reconstruction and studied the functional outcome in series of five cases where simple reconstructions are done.We did standard excision of sternum and ribs depending on the site. Immediate reconstruction was done using available myocutaneous flaps (TRAM flap, Pectoralis major muscle flap and polypropylene mesh). All cases had smooth postoperative course, had excellent coverage, chest wall stability and minimal donor site morbidity. All had a short hospital stay period (8-12 days) with good functional outcome. We do hereby propose nonrigid reconstruction for partial sternal defects as a good and safe alternative.

Anion directed structural diversity in zinc complexes with conformationally flexible quinazoline ligand: structural, spectral and theoretical studies.

In this paper, we report the synthesis, structure and photophysical studies of four new complexes of conformationally flexible 6-chloro-4-phenyl-2-(pyridin-2-yl)quinazoline ligand (L) with Zn(ii). The coordinating ability of the ligand and geometrical preferences of the resultant complexes are tuned by varying the anion of the metal salt as confirmed by structural and DFT studies. The choice of the metal salt (especially anion) directs the stabilisation of different conformations of the ligand arising out of twisting of the pyridyl ring with respect to the quinazoline ring, resulting in complexes with different nuclearity (monomer/dimer) as well as different coordination geometries (tetrahedral/trigonal bipyramidal/octahedral). Photophysical properties are also found to be tuned due to conformational changes on complexation. DFT studies on the ligand establish the conformationally stable forms as observed in the reported structures.

Is Greulich and Pyle standards of skeletal maturation applicable for age estimation in South Indian Andhra children?

INTRODUCTION: Now-a-day age determination has gained importance for various forensic and legal reasons. Skeletal age (SA) of a test population can be estimated by comparing with established standards of Greulich and Pyle (G-P). As this atlas has been prepared using data from upper-class children born between 1917 and 1942 in the USA and the applicability of these standards to contemporary populations has yet to be tested on Andhra children living in India. Hence, this study was aimed to assess the reliability of bone age calculated by G-P atlas in estimation of age in selected population. MATERIALS AND METHODS: A total of 660 children (330 girls, 330 boys) between ages 9 and 20 years were randomly selected from outpatient Department of Oral Medicine in GITAM Dental College, Andhra Pradesh. Digital hand-wrist radiographs were obtained and assessed for SA using G-P atlas and the difference between estimated SA and chronological age (CA) were compared with paired t-test and Wilcoxon signed rank test. RESULTS: G-P method underestimated the SA by 0.23 ± 1.53 years for boys and overestimated SA by 0.02 ± 2 years in girls and mild underestimation was noted in the total sample of about 0.1 ± 1.78 years. Spearman rank test showed significant correlation between SA and CA (r = 0.86; P < 0.001). CONCLUSION: This study concluded that G-P standards were reliable in assessing age in South Indian Andhra children of age 9-20 years with unknown CA.

Significance of weak interactions in imidazolium picrate ionic liquids: spectroscopic and theoretical studies for molecular level understanding.

The effects of interionic hydrogen bonding and π-π stacking interactions on the physical properties of a new series of picrate anion based ionic liquids (ILs) have been investigated experimentally and theoretically. The existence of aromatic (C2-HO) and aliphatic (C7-HO-N22 and C6-HO-N20) hydrogen bonding and π-π stacking interactions in these ILs has been observed using various spectroscopic techniques. The aromatic and aliphatic C-HO hydrogen bonding interactions are found to have a crucial role in binding the imidazolium cation and picrate anion together. However, the π-π stacking interactions between two successive layers are found to play a decisive role in tight packing in ILs leading to differences in physical properties. The drastic difference in the melting points of the methyl and propyl derivatives (mmimPic and pmimPic respectively) have been found to be primarily due to the difference in the strength and varieties of π-π stacking interactions. While in mmimPic, several different types of π-π stacking interactions between the aromatic rings (such as picrate-picrate, picrate-imidazole and imidazolium-imidazolium cation rings) are observed, only one type of π-π stacking interaction (picrate-picrate rings) is found to exist in the pmimPic IL. NMR spectroscopic studies reveal that the interaction of these ILs with solvent molecules is different and depends on the dielectric constant of the solvent. While an ion solvation model explains the solvation in high dielectric solvents, an ion-pair solvation model is found to be more appropriate for low dielectric constant solvents. The enhanced stability of these investigated picrate ILs compared with that of inorganic picrate salts under high doses of γ radiation clearly indicates the importance of weak interionic interactions in ILs, and also opens up the possibility of the application of picrate ILs as prospective diluents in nuclear separation for advanced fuel cycling process.

Generation of bioethanol and VFA through anaerobic acidogenic fermentation route with press mud obtained from sugar mill as a feedstock.

Acidogenic anaerobic fermentation route was explored for the production of bioethanol and volatile fatty acids (VFA) from the press mud (PM) obtained from sugar mill. Slurry was prepared from PM having 10% of total solids and the same was hydrolyzed under acidic thermal conditions. Both press mud slurry (PMS) and pre-treated press mud slurry (PTPMS) was used as feedstock with mixed microbial consortia (MMC) and enriched mixed microbial consortia (EMMC). Mix of bioethanol and VFA were obtained in all the four cases (PMS-MMC, PMS-EMMC, PTPMS-EMC and PTPMS-EMMC), but, bioethanol and VFA yield of 0.04 g/g and 0.27 g/g, respectively obtained from PTPMS with EMMC was found to be comparatively higher. Control experiments carried out with glucose yielded bioethanol and VFA of 0.042 g/g and 0.28 g/g, respectively demonstrating that the organism was using reducible sugars in the feedstock for the generation of bioethanol by simultaneously producing the VFA from COD.

Nucleosome structural changes induced by binding of non-histone chromosomal proteins HMGN1 and HMGN2.

Interactions between the nucleosome and the non-histone chromosomal proteins (HMGN1 and HMGN2) were studied by circular dichroism (CD) spectroscopy to elucidate structural changes in the nucleosome induced by HMGN binding. Unlike previous studies that used a nucleosome extracted from living cells, in this study we utilized a nucleosome reconstituted from unmodified recombinant histones synthesized in Escherichia coli and a 189-bp synthetic DNA fragment harboring a nucleosome positioning sequence. This DNA fragment consists of 5'-TATAAACGCC-3' repeats that has a high affinity to the histone octamer. A nucleosome containing a unique octamer-binding sequence at a specific location on the DNA was produced at sufficiently high yield for spectroscopic analysis. CD data have indicated that both HMGN1 and HMGN2 can increase the winding angle of the nucleosome DNA, but the extent of the structural changes induced by these proteins differs significantly. This suggests HMGN1 and HMGN2 would have different abilities to facilitate nucleosome remodeling.

Emission analysis of RE3+ (RE = Sm, Dy):B2O3-TeO2-Li2O-AlF3 glasses.

This article reports on the optical properties of 0.5% mol of Sm(3+), Dy(3+) ion-doped B2O3-TeO2-Li2O-AlF3 (LiAlFBT) glasses. The glass samples were characterized by optical absorption and emission spectra. Judd-Ofelt theory was applied to analyze the optical absorption spectra and calculate the intensity parameters and radiative properties of the emission transitions. The emission spectra of Sm(3+) and Dy(3+):LiAlFBT glasses showed a bright reddish-orange emission at 598 nm ((4)G5/2 → (6)H7/2) and an intense yellow emission at 574 nm ((4)F9/2 → (6)H13/2), respectively. Full width at half maximum (FWHM), stimulated emission cross section, gain bandwidth and optical gain values were also calculated to extend the applications of the Sm(3+) and Dy(3+):LiAlFBT glasses.

Effect of concentration on the photoluminescence properties of Sm3+ and Dy3+: cadmium lithium boro tellurite glasses.

Rare-earth (Sm3+ or Dy3+) ions doped cadmium lithium boro tellurite glasses have been prepared by melt quenching method for their spectral studies. From X-ray diffraction (XRD) patterns the glass amorphous nature has been confirmed. Vis-NIR absorption, excitation and emission spectra of these glasses have been analyzed systematically and also rare earth ion concentration is optimised Sm3+: CLiBT glasses have shown strong orange-reddish emission at 598 nm (4G5/2-->6H7/2) with an excitation wavelength lambda(exci) = 401 nm and Dy3+: CLiBT glasses have shown strong yellow emission at 574 nm (6F9/2-->6H13/2) with lambda(exci) = 451 nm.

Spectroscopic investigations of Er3+ :CdO-Bi2 O3-B2O3 glasses.

This article reports on the optical properties of Er3+ ions doped CdO-Bi2O3-B2O3 (CdBiB) glasses. The materials were characterized by optical absorption and emission spectra. By using Judd-Ofelt theory, the intensity parameters Ω(λ) (λ = 2, 4, 6) and also oscillatory strengths were calculated from the absorption spectra. The results were used to compute the radiative properties of Er3+ :CdBiB glasses. The concentration quenching and energy transfer from Yb3+ -Er3+ were explained. The stimulated emission cross-section, full width at half maximum (FWHM) and FWHM × σpE values are also calculated for all the Er3+ CdBiB glasses.

Synthesis and luminescence properties of Ca3Ga2Si3O12:RE3+ (RE = Eu/Tb) powder phosphors.

Rare earth ions (Eu(3+) or Tb(3+) )-activated Ca(3) Ga(2) Si(3) O(12) (CaGaSi) phosphors were synthesized by using a sol-gel method. Photoluminescence spectra of Eu(3+):CaGaSi phosphors exhibited five emission bands at 578, 592, 612, 652 and 701 nm, which were assigned to the transitions ((5)D(0) → (7)F(0), (7)F(1,)(7)F(2), (7)F(3) and (7)F(4)), respectively, with an excitation wavelength of λ(exci) = 392 nm. Among these, the transition (5) D(0) → (7) F(2) (612 nm) displayed bright red emission. In the case of Tb(3+):CaGaSi phosphors, four emission bands were observed at 488 ((5)D(4) → (7)F(6)), 543 ((5)D(4) → (7)F(5)), 584 ((5)D(4) → (7)F(4)) and 614 nm ((5)D(4) → (7) F(3) ) from the measurement of PL spectra with λ(exci) = 376 nm. Among these, the transition (5)D(4) → (7) F(5) at 543 nm displayed bright green emission. The structure and morphology of the phosphors were studied from the measurements of X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDAX) results.

Optical characterization of Eu3+ and Tb3+ ions doped cadmium lithium alumino fluoro boro tellurite glasses.

This article reports on the development and spectral results of Eu(3+) and Tb(3+) ions doped cadmium lithium alumino fluoro boro tellurite (CLiAFBT) glasses in the following composition. 40TeO2-30B2O3-10CdO-10Li2O-10AlF3 (Hostglass) (40-x)TeO2-30B2O3-10CdO-10Li2O-10AlF3-xEu2O3 (40-x)TeO2-30B2O3-10CdO-10Li2O-10AlF3-xTb4O7 where x=0.25, 0.50, 0.75, 1.0, 1.25 mol%. Glass amorphous nature and thermal properties have been studied using the XRD and DSC profiles. From the emission spectra of Eu(3+):glasses, five emission transitions have been observed at 578 nm, 592 nm, 612 nm, 653 nm, 701 nm and are assigned to the transitions (5)D(0)→(7)F(0), (7)F(1,)(7)F(2), (7)F(3) and (7)F(4), respectively, with λ(exci)=392 nm ((7)F(0)→(5)L(6)). In case of Tb(3+):glasses, four emission transitions ((5)D(4)→(7)F(6,)(7)F(5), (7)F(4) and (7)F(3)) are observed at 488 nm, 543 nm, 584 nm and 614 nm, respectively, with λ(exci)=376 nm. Decay curves and energy level diagrams have been plotted to evaluate the life times and to analyze the emission mechanism.

Focal clinical and electroencephalographic features in patients with juvenile myoclonic epilepsy.

OBJECTIVE: To identify prevalence and factors associated with occurrence of focal clinical and electroencephalogram (EEG) abnormalities in patients with juvenile myoclonic epilepsy (JME). MATERIALS AND METHODS: Clinical asymmetries in the seizures and focal EEG abnormalities were analyzed in 266 patients with JME. RESULTS: All the patients had myoclonic jerks (MJ) and generalized tonic-clonic seizures (GTCS); 56 (21%) had absence seizures. Asymmetry in clinical seizures was reported in 45 (16.9%) and focal EEG abnormalities were noted in 92 (45.5%) patients. Amplitude asymmetry or focal onset of generalized discharges was noted in 41 (44.6%) and independent focal EEG abnormalities in 30 (32.6%) patients. A statistically significant association was seen with the presence of GTCS and MJ (P = 0.007), a family history of epilepsy (P = 0.001) and drug resistance (P = 0.04) and the occurrence of focal EEG abnormalities. CONCLUSION: Patients with JME showed focal clinical and EEG features. These features should not be misinterpreted as indicative of partial epilepsy.

Surface-phosphorylated copolymer promotes direct bone bonding.

The bone bonding potential of surface-phosphorylated poly (2-hydroxyethyl methacrylate-co-methyl methacrylate) [poly (HEMA-co-MMA)] has been investigated and compared with commercially available poly (methyl methacrylate) bone cement (CMW1 radiopaque, Depuy; Johnson & Johnson, Blackpool, Lancashire, England, United Kingdom) as control. Poly (HEMA-co-MMA) is synthesized by free radical-initiated copolymerization and surface functionalized by phosphorylation. The X-ray photoelectron spectroscopy confirms the presence of surface-bound phosphate groups on poly (HEMA-co-MMA). The surface-phosphorylated poly (HEMA-co-MMA) promotes in vitro biomineralization, cell viability, cell adhesion, and expression of bone-specific markers such as osteocalcin and alkaline phosphatase. The bone implantation study performed in rabbits as per ISO 10993-6; 1994 (E) shows that surface-phosphorylated poly (HEMA-co-MMA) elicits bone bonding and new bone formation. New woven bone trabeculae are formed at the defect site of surface-phosphorylated poly (HEMA-co-MMA) within 1 week, while for control sample, inflammatory cells--predominantly, macrophages, fibroblasts, and fibrocytes--are present at the cortical margins around the defect. The 4 and 12 weeks postimplantation results show that the major part of the defects around the surface-phosphorylated poly (HEMA-co-MMA) implant is bridged with new woven bone, with significant remodeling (evident from resorption bays) along both the margins of the defect, but for control implants, the defects are only partially closed, with slight remodeling along the margins, but most of them are separated by fibrous tissue.

Second lumbrical and interossei latency difference in Carpal Tunnel Syndrome.

OBJECTIVE: To evaluate the diagnostic value of second lumbrical and interossei distal motor latency difference (2LIDMLD) in diagnosing CTS of different electro-physiological grades of CTS. METHODS: 2LIDMLD was standardized in 120 hands of healthy controls. Subjects with clinically diagnosed CTS and CTS with incidental polyneuropathy were prospectively evaluated with 2LIDMLD in addition to other standard diagnostic tests. Sensitivities of these tests were compared in patients with CTS of varying grades of severity and CTS associated with polyneuropathy. RESULTS: Two hundred and fifty hands of 130 patients met the clinical criteria for CTS. Sensitivity and specificity of 2LIDMLD, palm-wrist distal sensory latency difference (PWDSLD), and median distal motor latency (MDML) were 85.60% and 96.67%, 68.80% and 96.10%, 60.80% and 97%, respectively. Sensitivity of 2LIDMLD in mild CTS was similar to that of PWDSLD. In severe CTS, and CTS with polyneuropathy, 2LIDMLD was the most sensitive test. It was the only test of localizing value in 16% of hands with severe CTS, when all other methods failed due to absent median motor and sensory responses. CONCLUSIONS: 2LIDMLD is a sensitive, specific for diagnosis of all grades of CTS. It is an accurate and reliable method that helps especially in diagnosis of severe CTS and CTS associated with polyneuropathy, when other standard localized tests fail. SIGNIFICANCE: The second lumbrical is relatively less affected in severe carpal tunnel syndrome and median to ulnar comparison, using 2LIDMLD, appears to be a reliable and a valuable technique in the localization of severe CTS and CTS associated with polyneuropathy, especially when the median sensory or motor responses are absent on routine conduction studies.

Clinical and electroencephalographic study of first-degree relatives and probands with juvenile myoclonic epilepsy.

PURPOSE: Juvenile myoclonic epilepsy (JME) is a common, well-defined epileptic syndrome. This study aims to examine the clinical and EEG features of probands with JME and to identify the incidence of different types of idiopathic generalized epilepsies (IGEs) and IGE trait in first-degree relatives. METHODS: Clinical and EEG data were collected from 132 first-degree relatives and 31 probands with JME. The data were analyzed using descriptive statistics, chi-square test, t-test and ANOVA. RESULTS: All probands had a history of generalized tonic clonic seizures (GTCS) and myoclonic jerks; 25.8% had a history of absence seizures. Family history of epilepsy was noted in 42% and epilepsy in first-degree relatives was reported in 38.7%. We found JME in 44% of the symptomatic first-degree relatives. The incidence of epilepsy was higher in siblings (19%) than in offspring (8%) or parents (4%), the difference between the groups being significant (p < 0.05). IGE trait was noted in 6% of the asymptomatic first-degree relatives. Finally, IGE features were found in 61%. Subjects with IGE features were younger (mean age 19.6 years) than those without IGE features (mean age 32.4 years) and the difference between the groups was significant. CONCLUSION: The incidence of different kinds of IGEs and typical EEG trait is high in first-degree relatives of JME probands. IGE features were noted in 61% of the families. JME is the most common type of IGE and IGE features were found to be more frequent among siblings than parents. These findings confirm familial susceptibility to IGE.