Minor Bands Research Articles

Profil Bobot Molekul Protein, Cemaran Logam Berat Timbal (Pb) Dan Kadmium (Cd), Serta Bakteri Escherichia coli Pada Ekstrak Cair Ikan Gabus (Channa striata)

The Snakehead fish extract is one of the fish extracts that has many benefits and has been used in the health sector such as emulsifiers, skin health drugs, helping muscle formation and growth, accelerating wound healing, maintaining fluid balance in blood vessels, improving poor nutrition, and being healthy. for digestion so that the quality characteristics of the extract need to be researched and maintained to be used. This study aims to determine the quality characteristics of the liquid extract of snakehead fish (Channa striata) based on quality parameters such as protein molecular weight profile, heavy metal contamination of lead (Pb), and cadmium (Cd), and bacterial contamination of Escherichia coli. Snakehead fish extract was obtained using the steaming extraction method at a temperature of 60oC, for 6 hours to obtain albumin levels of 12.549 mg/g, protein molecular weight profile analysis detected 7 major bands and 1 minor band in the molecular weight range 19.05 kDa - 92, 72 kDa, where the molecular weight of albumin protein is suspected to be in band number 3 53.72 kDa, E.coli bacteria contamination < 3 APM/g and heavy metals lead (Pb) and cadmium (Cd) were not detected.

Luminescent Zn Halide Complexes with 2-(2-Aminophenyl)benzothiazole Derivatives

We report a comparative study of coordination behaviour of 2-(2-aminophenyl)benzothiazole (NH2-pbt) and its phosphorus-containing derivative, α-aminophosphine oxide (PCNH-pbt), towards zinc halides. The corresponding coordination compounds [Zn(L)2Hal2] (L = PCNH-pbt, Hal = Cl, 1 and Hal = Br, 2) and [Zn(L’)Hal2] (L’ = NH2-pbt, Hal = Cl, 3 and Hal = Br, 4) were obtained as single phases. As evidenced by single-crystal X-ray diffraction analysis, L’ ligand coordinates to Zn in a chelate manner via two N atoms. Despite a similar coordination mode in complexes 3 and 4, the spatial geometry of the ligand differs notably, which implies a relatively high flexibility of NH2-pbt. The L ligand exhibits another coordination mode, binding with Zn only via the oxygen of the P=O group. The differences in the structures of NH2-pbt, 3 and 4, and their counterparts, PCNH-pbt, 1 and 2, induce differences in their solid-state photoluminescence properties. The former group of the compounds exhibits conventional single-band emission, while the latter group reveals two bands. The minor band at 450 nm is ascribed to a radiative transition for the regular amine species, while the major band at 520–550 nm can be associated either with the proton-transferred imine species (ESIPT mechanism) or with a charge transfer state (TICT) with a different geometry.

First Principles Calculations of Co2MSi (M=Cr, Mn, Fe) Heusler Alloys

The present work describes the electronic structure, magnetic and elastic properties of ordered Co2MSi (M = Cr, Mn, Fe) Heusler alloys in L21 structure calculated using density functional theory within generalized gradient approximation. The calculated band structures, density of states and magnetic moments have been discussed. The magnetic moment values obtained in present study follow the Slater-Pauling rule. A small band gap in the minority band structure at the Fermi level suggests half-metallicity. Hundred percentage spin polarization in this ordered structure implies that these materials possess ferromagnetism. All the three materials satisfy stability criteria in terms of elastic constants and are predicted to have ductile behaviour based on the ratio of shear to bulk modulus.

Molecular Environment Effects That Modulate the Photophysical Properties of Novel 1,3-Phosphinoamines Based on 2,1,3-Benzothiadiazole.

We report synthesis, crystal structure, and photophysical properties of novel 1,3-phosphinoamines based on 4-amino-2,1,3-benzothiadiazole (NH2-btd): Ph2PCH(Ph)NH-btd (1) and Ph2P(E)CH(Ph)NH-btd, (E = O (2α and 2β·thf), S (3), Se (4)). Chalcogenides 2–4 exhibit bright emissions with a major band at 519–536 nm and a minor band at 840 nm. According to TD-DFT calculations, the first band is attributed to fluorescence, while the second band corresponds to phosphorescence. In the solid state, room temperature quantum yield reaches 93% in the case of the sulphide. The compounds under study feature effects of the molecular environment on the luminescent properties, which manifest themselves in fluorosolvatochromism as well as in a luminescent response to changes in crystal packing and in contributions to aggregation effects. Specifically, transformation of solid 2β·thf to solvate-free 2β either by aging or by grinding causes crystal packing changes, and, as a result, a hypsochromic shift of the emission band. Polystyrene films doped with 2 reveal a bathochromic shift upon increasing the mass fraction from 0.2 to 3.3%, which is caused by molecular aggregation effects.

Identification of major carotenoids from green alga Tetraspora sp. CU2551: partial purification and characterization of lutein, canthaxanthin, neochrome, and β-carotene.

The green algae Tetraspora sp. CU2551 was previously identified as a strain with high potential for biohydrogen production; however, its algal biomass characteristics changed from green to reddish orange within 43days of biohydrogen production. The crude pigments were extracted, partially purified, and characterized by chemical determination. The present study focused on elucidating the carotenoid composition of the selected green alga Tetraspora sp. CU2551. The pigment extract was partially purified and fractionated using thin layer chromatography, and yielded two major and two minor carotenoid bands. The fractions were confirmed by high-performance liquid chromatography with a diode array detector (HPLC-DAD) before being identified and confirmed using Liquid Chromatograph-Quadrupole Time of Flight-Mass Spectrometry (LC-QTOF-MS). The spectral data of these fractions revealed four sub-fractions of interest that were lutein, canthaxanthin, neochrome, and β-carotene, which had percentages in the crude extracts of 30.57%, 25.47%, 7.89%, and 0.71%, respectively. Lutein and canthaxanthin were found to be the major carotenoid pigments present. Our findings in this present study are the first reporting of Tetraspora sp. CU2551 as a potential alternate source for carotenoid pigment production.

Self-assembly of magnetic Co atoms on stanene

We have investigated magnetic Co atoms self-assembled on ultraflat stanene on Cu(111) substrate by utilizing scanning tunneling microscopy/spectroscopy (STM/STS) in conjunction with density functional theory (DFT). By means of depositing Co onto the stanene/Cu(111) held at 80 K, Co atoms have developed into monomer, dimer, and trimer structures containing one, two, and three Co atoms, respectively. As per atomically resolved topographic images and bias-dependent apparent heights, the atomic structure models based on Sn atoms substituted by Co atoms have been deduced, which are in agreement with both self-consistent DFT calculations and STM simulations. Apart from that, the projected density of states has revealed a maximum at around $\ensuremath{-}0.5$ eV from the Co-3${d}_{3{z}^{2}\ensuremath{-}{r}^{2}}$ minority band, which contributes predominately to the peak feature at about $\ensuremath{-}0.3$ eV in tunneling conductance $(dI/dU)$ spectra taken at the Co atomic sites. As a result of the exchange splitting between the $\mathrm{Co}\text{\ensuremath{-}}3d$ majority and minority bands, there are nonzero magnetic moments, including about $0.60{\ensuremath{\mu}}_{B}$ in monomer, $0.56{\ensuremath{\mu}}_{B}$ in dimer, and $0.29{\ensuremath{\mu}}_{B}$ in trimer of the Co-atom assembly on the stanene. Such a magnetic Co-atom assembly, therefore, could provide the vital building blocks to stabilize the local magnetism on two-dimensional stanene with nontrivial topological properties.

Solution structures and ultrafast vibrational energy dissipation dynamics in cyclotetramethylene tetranitramine.

Steady-state and time-resolved infrared (IR) studies of cyclotetramethylene tetranitramine (HMX) were carried out, using the asymmetric nitro-stretch as probe, to investigate its solution structures and vibrational energy transfer processes in pure dimethyl sulfoxide (DMSO) and in a DMSO/water mixture. A linear IR spectrum in the nitro-stretching mode region shows two major bands and one minor band in DMSO but changes to the two major bands mainly picture when adding water as an antisolvent of HMX, suggesting a transition from well-solvated and less perfect β-conformation to a less-solvated and close-to-perfect β-conformation. The latter bears a similar asymmetric nitro-stretch vibration profile to the β-polymorph in the crystal form. Density functional theory computations of the nitro-stretching vibrations suggest that HMX in DMSO may be in a NO2 group rotated β-conformation. Two-dimensional IR cross-peak intensity reveals intramolecular energy transfer between the axial and equatorial nitro-groups in the β-HMX on the ps time scale, which is slightly faster in the mixed solvent case. The importance of water as an antisolvent in influencing the equilibrium solvation structure, as well as the vibrational and orientational relaxation dynamics of HMX, is discussed.

Symmetry of Wavefunction at the Interface of Fe/MgO Magnetic Tunneling Junction

We measured the anisotropy of Magnetic Compton profiles (MCP) in the Fe/MgO multilayers and compared it with band structure calculations. At the Fe/MgO interface, the |m| = 1 state in the minority band is suppressed, which in turn promotes the spin-polarized occupation of the |m| = 1 state. At the Fe/FeO interface of intentionally oxidized Fe/MgO multilayers, the occupations of the magnetic quantum number are almost equal (spherical) in the majority band and minority band, and therefore, the spin-polarization occupancy is also almost equal (spherical). These results contribute to the material design for MTJs as high-performance spintronic devices.

Heat-Stable Antifungal Factor and Expression Patterns of Protease by Chitinase-Producing Bacterium, Pedobacter sp. PR-M6

This study was conducted to investigate the protease expression patterns of the novel chitinase-producing bacterium Pedobacter sp. PR-M6. Protease were detected on SDS-PAGE gel as condition of 4℃, 25℃ and 37℃ to activate of enzymes obtained from incubation of LB, NB and 1% skim milk medium at 4℃, 20℃ and 30℃ after 21 days of incubation, respectively. Pedobacter sp. PR-M6 displayed proteolytic activity on SDS-PAGE gels containing 0.1% (w/v) gelatin, and protease isozymes of PR-M6 were expressed as two major bands (P7 and P8) and seven minor bands (P1, P2, P3, P4, P5, P6, and P9). Protease isozymes of PR-M6 were inhibited at 4℃ and 25℃. The two protease isozymes P5 and P6 were newly expressed in the LB culture medium at 20℃. To investigate the properties of a heat-stable antifungal factor (HSAF), PR-M6 stain was cultured to obtain the products of biosynthesis for incubation in LB medium. HSAF exhibited active biosynthesis at 20℃ for incubation in LB medium. Crude HASF obtained from LB20 medium showed hyphal growth inhibition of Rhizoctonia solani. Inhibition rate of R. solani growth was as high as 67% at 24 h and 47.8% at 48 h after incubation with 1,000 ppm of crude HSAF. Trypan blue stained the inside of the edge for destructed R. solani cell walls after crude HSAF treatment. These results indicated that HSAF and protease from Pedobacter sp. PR-M6 could be used as biocontrol agents against phytopathogens in agriculture.

Aquaporin (AQP) channels in the spiny dogfish, Squalus acanthias I: Characterization of AQP3 and AQP15 function and expression, and localization of the proteins in gill and spiral valve intestine.

Complementary DNAs (cDNAs) for two aquaporin water channel genes (AQP3 and AQP15) were amplified cloned and sequenced to initiate this study. Northern blot analysis was carried out to confirm the mRNA sizes of these AQP genes with AQP3 mRNA bands exhibiting sizes of 1.2 and 1.6k bases and AQP15 had a mRNA band of 2.1k bases. Northern blot analysis was also performed on kidney and esophagus total RNA samples from fish acclimated to 75%, 100% or 120% seawater (SW). The level of AQP15 mRNA expression was shown to significantly decrease following salinity acclimation from 100 to 120% SW. An opposite but non-significantly different trend was observed for AQP3 mRNA levels. Full length cDNAs were then used to generate AQP3 and AQP15 mRNAs for microinjection into Xenopus oocytes. Both AQP3- and AQP15- microinjected oocytes exhibited significantly elevated apparent water permeability compared to control oocytes at neutral pH. The apparent water permeability was mercury-inhibitable, significantly so in the case of AQP3. AQP3 microinjected oocytes showed pH sensitivity in their apparent water permeability, showing a lack of permeability at acidic pH values. The Carboxyl-terminal derived amino acid sequences of AQP3 and AQP15 were used to generate rabbit affinity-purified polyclonal antibodies. Western blots with the antibodies showed a band of 31.3kDa for AQP3 in the kidney, with minor bands at 26, 24 and 21kDa. For AQP15 a band of 26kDa was seen in gill and kidney. Fainter bands at 28 and 24kDa were also seen in the kidney. There was also some higher molecular weight banding. None of the bands were seen when the antibodies were pre- blocked with their peptide antigens. Immunohistochemical localization studies were also performed in the gill and spiral valve intestine. In the gill, AQP15 antibody staining was seen sporadically in the membranes of surface epithelial cells of the secondary lamellae. Tyramide amplification of signals was employed in the spiral valve intestine. Tyramide-amplified AQP3 antibody staining was observed in the basal membrane of the invaginated epithelial cell layer of secondary intestinal folds in luminal surface of either the side wall of the spiral valve intestine or in internal valve tissue 'flaps'. For the AQP15 antibody, tyramide-amplified staining was instead found on the apical and to a lesser extent the lateral membranes of the same invaginated epithelial cell layer. The localization of AQP3 and AQP15 in the spiral valve intestine suggests that a trans-cellular water absorption pathway may exist in this tissue.

H2O in omphacite of quartz and coesite eclogite from Erzgebirge and Fichtelgebirge, Germany

AbstractMajor and trace elements in omphacite, including hydrogen, were determined in eclogites from two Variscan basement complexes in Germany: Erzgebirge (EG) and Fichtelgebirge (FG). Erzgebirge eclogite is derived from three units, showing different peak pressure (P) and temperature (T) conditions (Unit 1: 840–920°C/≥30 kbar, Unit 2: 670–730°C/24–26 kbar, Unit 3: 600–650°C/20–22 kbar). The peak conditions of FG eclogite (690–750°C/25–28 kbar) resemble those of EG Unit 2. Coesite eclogite occurs in EG Unit 1, and quartz eclogite in all other units. Omphacite from all samples shows four infrared (IR) absorption bands. Two prominent, sharp bands occur at 3,455 ± 10 cm−1 (band II) and 3,522 ± 10 cm−1 (band III). Band II is usually more prominent than band III, except for few samples with low jadeite content. A further, broad band is centred between 3,270 and 3,370 cm−1 (band I) and a fourth, minor band at 3,611–3,635 cm−1 (band IV). Bands II and III are due to hydrogen bound as structural OH− ions in omphacite. In most cases, this also applies to band IV. However, some spectra with extremely large type IV bands reflect phengite inclusions. The ambiguous band I may be due to different H2O species (molecular water, structural OH, and water in phengite). Omphacite of quartz eclogite has lower contents of TiO2, Zr, Hf, and REE, compared with that from coesite eclogite. By contrast, omphacite in quartz eclogite from both EG (H2O sample averages: 465–852 ppm) and FG (546–1,089 ppm) contains the same amount of structural OH (concentrations given in wt.‐ppm H2O) as omphacite in coesite eclogite (492–1,140 ppm). The obtained difference in the garnet‐omphacite H2O partition coefficient between quartz (0.01–0.03) and coesite eclogite (0.08–0.11) results from different H2O contents in garnet (coesite eclogite: 50–150 ppm; quartz eclogite: <2–50 ppm; Gose & Schmädicke, 2018). The total content of structural OH in omphacite is unrelated to its major and trace element composition. However, treating the individual IR bands separately, a relation between OH and mineral composition is observed. The OH amount defined by band II is positively correlated to Ti and tetrahedral Al, and that of band III shows a positive correlation with Ca and a negative one with Na (and jadeite). Both the total OH content of omphacite and the partial contents deduced from individual IR bands are unrelated to PT conditions. This implies that omphacite incorporated its structural H2O mainly in the quartz stability field, presumably during initial omphacite growth. Conversely, most OH in garnet was derived from the final breakdown of the last remaining calcic amphibole close to or within the coesite stability field. Our data suggest that coesite eclogite is able to transport a significant amount of H2O (average 550 ppm, maximum 730 ppm), corresponding to that in 3–4 vol.% calcic amphibole, via subduction to depths beyond 100 km. However, the majority of water liberated by dehydration reactions during subduction, including the breakdown of 5–10 vol.% eclogite facies and >10 vol.% pre‐eclogitic hydrous minerals, is not preserved in eclogite but liberated to the mantle wedge.

Introduction to the special issue on hazardous faults in Latin America

This work presents the results of a study about the effects of brittle deformation on the distribution of porosity and permeability in poorly consolidated sandstones. The study was carried out in an outcrop of the Resende Formation, located in the Volta Redonda Basin (State of Rio de Janeiro, Brazil), which has been described by other authors as a geomechanical analog of poorly consolidated Maastrichtian sandstone reservoirs in the Campos Basin. This outcrop is composed of fluvial deposits of poorly consolidated sandstones interlayered with green siltstones, characteristics of the Resende Formation. According to previous works on the outcrop, the deformation that operated in these deposits results from the superposition of three of the tectonic events that occurred in the Volta Redonda Basin – a right-lateral strike-slip deformational event (TD), a left-lateral strike-slip deformational event (TS), and finally a Holocene extensional event (E2). These events produced a graben structure, several minor secondary faults and deformation band zones. To better understand how the evolving process of those structures affected the distribution of the original porosity and permeability through the outcrop, a series of finite element numerical models were done in this study, based on the continuum mechanics. In these models, only the final extensional tectonic event in the Volta Redonda Basin, E2, was considered. Results showed a higher volumetric loss caused by deformational compaction in the hanging wall of the main outcrop structures. These models are consistent with the permeability distribution measured in the outcrop and with the observed rock-staining patterns derived from the iron-precipitation process associated with zones of restricted fluid flow, and reveal notable differences concerning tectonic strain distribution between the hanging wall and footwall blocks. Although the uncertainty in the geomechanical parameters is a challenge, the technique can improve geological modeling of reservoirs for exploratory purposes, especially in poorly consolidated and fractured sandstones related to the extensional structural style of Brazilian offshore basins.

Numerical modeling of brittle tectonic deformation in poorly consolidated sandstones

This work presents the results of a study about the effects of brittle deformation on the distribution of porosity and permeability in poorly consolidated sandstones. The study was carried out in an outcrop of the Resende Formation, located in the Volta Redonda Basin (State of Rio de Janeiro, Brazil), which has been described by other authors as a geomechanical analog of poorly consolidated Maastrichtian sandstone reservoirs in the Campos Basin. This outcrop is composed of fluvial deposits of poorly consolidated sandstones interlayered with green siltstones, characteristics of the Resende Formation. According to previous works on the outcrop, the deformation that operated in these deposits results from the superposition of three of the tectonic events that occurred in the Volta Redonda Basin – a right-lateral strike-slip deformational event (TD), a left-lateral strike-slip deformational event (TS), and finally a Holocene extensional event (E2). These events produced a graben structure, several minor secondary faults and deformation band zones. To better understand how the evolving process of those structures affected the distribution of the original porosity and permeability through the outcrop, a series of finite element numerical models were done in this study, based on the continuum mechanics. In these models, only the final extensional tectonic event in the Volta Redonda Basin, E2, was considered. Results showed a higher volumetric loss caused by deformational compaction in the hanging wall of the main outcrop structures. These models are consistent with the permeability distribution measured in the outcrop and with the observed rock-staining patterns derived from the iron-precipitation process associated with zones of restricted fluid flow, and reveal notable differences concerning tectonic strain distribution between the hanging wall and footwall blocks. Although the uncertainty in the geomechanical parameters is a challenge, the technique can improve geological modeling of reservoirs for exploratory purposes, especially in poorly consolidated and fractured sandstones related to the extensional structural style of Brazilian offshore basins.

Suppression of Co-Cr antisite defect and robust half metallicity in CoMCrAl (M = Mn, Fe) Heusler alloys

Quaternary alloys CoMnCrAl, CoFeCrAl and their ternary counterpart Co2CrAl are studied experimentally and theoretically to explore the effects of the substitution of Mn or Fe atoms for part of Co atoms in Co2CrAl. It is found that CoMnCrAl or CoFeCrAl has a magnetization 0.92 μB/f.u. or 1.96 μB/f.u. respectively in agreement with the Slater–Pauling (SP) rule, different from the parent ternary alloy Co2CrAl whose magnetization significantly deviates. The combination of experimental and theoretical results suggests that the formation of Co-Cr antisite defect is suppressed by partially substituting Mn or Fe for Co. The main disorder defects in CoMnCrAl are Cr-Al and Mn-Cr antisites, Fe-Cr and Cr-Al antisites in CoMnCrAl. Since these antisite defects only have small effect on the minority band structure, the half metallicity of CoMnCrAl or CoFeCrAl is expected to have much better tolerance for atomic disorder, compared with Co2CrAl. A negative temperature coefficient of resistance for a long temperature range about 10–273 K has been found exclusively for CoMnCrAl compound. Quaternary alloy CoMnCrAl or CoFeCrAl is found to be compensated ferrimagnetism with a relative low magnetization but a Curie temperature (TC) significantly higher room temperature (RT), whose magnetization are relatively low, but TC higher than the ternary alloy Co2CrAl. Considering their low magnetization, decently high TC and the robust half metallicity, these two quaternary alloys may have important applications in spintronic devices.

Subpicosecond metamagnetic phase transition in FeRh driven by non-equilibrium electron dynamics

Femtosecond light-induced phase transitions between different macroscopic orders provide the possibility to tune the functional properties of condensed matter on ultrafast timescales. In first-order phase transitions, transient non-equilibrium phases and inherent phase coexistence often preclude non-ambiguous detection of transition precursors and their temporal onset. Here, we present a study combining time-resolved photoelectron spectroscopy and ab-initio electron dynamics calculations elucidating the transient subpicosecond processes governing the photoinduced generation of ferromagnetic order in antiferromagnetic FeRh. The transient photoemission spectra are accounted for by assuming that not only the occupation of electronic states is modified during the photoexcitation process. Instead, the photo-generated non-thermal distribution of electrons modifies the electronic band structure. The ferromagnetic phase of FeRh, characterized by a minority band near the Fermi energy, is established 350 ± 30 fs after the laser excitation. Ab-initio calculations indicate that the phase transition is initiated by a photoinduced Rh-to-Fe charge transfer.

Finite-temperature full random-phase approximation of bandgap narrowing in quasi-neutral regions: Theory including nonparabolicity and application to silicon and InGaAs

The bandgap narrowing (BGN) in quasi-neutral regions of semiconductors is calculated in a finite-temperature full random-phase approximation formalism based on a simple isotropic dispersion model including band nonparabolicity. The total quasi-particle shift (QPS) is determined by the exchange-correlation self-energy of the free carriers and the correlation energy of the interaction between carriers and ionized dopants. At cryogenic temperatures, the latter part results in giant shifts of the minority band edge in n-type semiconductors with a large ratio of valence to conduction band density of states, as often present in III–V materials. However, at room temperature, the BGN does not exceed common values. The reason for this behavior is explained analytically. Whereas the exchange-correlation energy of free carriers is known to be insensitive to band structure details, the nonparabolicity of the conduction band (CB) has a strong effect on the ionic QPS of the minority carriers in n-type III–V materials. It strongly reduces the BGN at cryogenic temperatures compared to the case of a parabolic CB. This is demonstrated numerically and also analytically for n-type InGaAs. The BGN in n-type silicon becomes independent of temperature at high concentrations, but in p-type silicon, a weak temperature dependence re-emerges above the Mott density, which also can be attributed to the ionic QPS of the minority electrons. The calculated BGN for quasi-neutral regions in silicon is in good agreement with earlier photoluminescence and more recent photo-conductance measurements.

Efficiency enhancement of CZTSe solar cell using CdS(n)/(AgxCu1–x)2ZnSnSe4 (p) /Cu2ZnSnSe4 (p+) structure

Direct bandgap Cu2ZnSnSe4 (CZTSe) material is a promising absorber for thin film photovoltaics due to its affordable production cost and ecofriendly constituents. However, bulk defects, small grain size, short minority carrier lifetime and band bending at CZTSe/Mo (back contact) interface limit the performance of CZTSe solar cells. To overcome these issues, we design a single junction CdS(n)/ (AgxCu1–x)2ZnSnSe4 (p) /Cu2ZnSnSe4 (p + ) solar cell where we use (AgxCu1–x)2ZnSnSe4 (ACZTSe) as the main absorber layer. We have chosen the carrier density of each layer in a such way that ACZTSe becomes depleted and generated minority are collected efficiently. In our design, we utilize CZTSe as the back surface field layer to prevent surface recombination and indium doped tin oxide (ITO) as the back electrode to avoid band bending and increase the open circuit voltage. Additionally, we optimize the thicknesses of different layers and achieve a maximum efficiency of 18.63% including Shockley-Read-Hall, radiative and surface recombination mechanisms. The photo conversion efficiency (PCE) of our designed solar cell is 6% higher (12.6% vs 18.63%) than that of the best reported selenium rich CZTSe solar cell. The design concept proposed in this work would help in harvesting solar energy efficiently from next generation CZTSe solar cells.

Room-temperature intrinsic ferromagnetism in epitaxial CrTe2 ultrathin films

While the discovery of two-dimensional (2D) magnets opens the door for fundamental physics and next-generation spintronics, it is technically challenging to achieve the room-temperature ferromagnetic (FM) order in a way compatible with potential device applications. Here, we report the growth and properties of single- and few-layer CrTe2, a van der Waals (vdW) material, on bilayer graphene by molecular beam epitaxy (MBE). Intrinsic ferromagnetism with a Curie temperature (TC) up to 300 K, an atomic magnetic moment of ~0.21 {mu }_{{rm{B}}}/Cr and perpendicular magnetic anisotropy (PMA) constant (Ku) of 4.89 × 105 erg/cm3 at room temperature in these few-monolayer films have been unambiguously evidenced by superconducting quantum interference device and X-ray magnetic circular dichroism. This intrinsic ferromagnetism has also been identified by the splitting of majority and minority band dispersions with ~0.2 eV at Г point using angle-resolved photoemission spectroscopy. The FM order is preserved with the film thickness down to a monolayer (TC ~ 200 K), benefiting from the strong PMA and weak interlayer coupling. The successful MBE growth of 2D FM CrTe2 films with room-temperature ferromagnetism opens a new avenue for developing large-scale 2D magnet-based spintronics devices.

VB-Ea-5: a lytic bacteriophage against multi-drug-resistant Enterobacter aerogenes.

Background and Objectives:Multi-drug-resistant Enterobacter aerogenes is associated with various infectious diseases that cannot be easily treated by antibiotics. However, bacteriophages have potential therapeutic applications in the control of multi-drug-resistant bacteria. In this study, we aimed to isolate and characterize of a lytic bacteriophage that can lyse specifically the multi-drug-resistant (MDR) E. aerogenes.Materials and Methods:Lytic bacteriophage was isolated from Qaem hospital wastewater and characterized morphologically and genetically. Next-generation sequencing was used to complete genome analysis of the isolated bacteriophage.Results:Based on the transmission electron microscopy feature, the isolated bacteriophage (vB-Ea-5) belongs to the family Myoviridae. vB-Ea-5 had a latent period of 25 minutes, a burst size of 13 PFU/ml, and a burst time of 40 min. Genome sequencing revealed that vB-Ea-5 has a 135324 bp genome with 41.41% GC content. The vB-Ea-5 genome codes 212 ORFs 90 of which were categorized into several functional classes such as DNA replication and modification, transcriptional regulation, packaging, structural proteins, and a host lysis protein (Holin). No antibiotic resistance and toxin genes were detected in the genome. SDS-PAGE of vB-Ea-5 proteins exhibited three major and four minor bands with a molecular weight ranging from 18 to 50 kD.Conclusion:Our study suggests vB-Ea-5 as a potential candidate for phage therapy against MDR E. aerogenes infections.

Analysis and perception of a viscoelastic, frequency-dependent Finite-Difference Time Domain damping model of a drum

This study investigates the influence of viscoelastic damping parameters in a Viscoelastic Finite Difference Time Domain (FDTD) model on the sound of a drum head. Due to the strong nonlinearity between the complex, frequency-dependent Young’s modulus as a model input parameter and resulting damping frequencies and damping strength, this relation can no longer be analyzed analytically. One reference and eight altered membranes are constructed. Integrating the sound into minor third bands, nonlinear mode couplings due to viscoelasticity are found, relating to the real part of the Young’s modulus as well as to the Laplace-Transform parameter of the FDTD model. Furthermore, the perception of the sounds was investigated. The results are compared to the physical observation, showing variations in brightness and pitch. Hereby, the perception can be described as proportional to the physical analysis, as long as the variation of the Laplace parameter in one or more damped frequencies does not lead to a huge difference in the sounds decay time, which seems to distract the attention from other acoustical characteristics.