Population genetic implications from sequence variation in four Y chromosome genes

Some insight into human evolution has been gained from the sequencing of four Y chromosome genes. Primary genomic sequencing determined gene SMCY to be composed of 27 exons that comprise 4,620 bp of coding sequence. The unfinished sequencing of the 5' portion of gene UTY1 was completed by primer walking, and a total of 20 exons were found. By using denaturing HPLC, these two genes, as well as DBY and DFFRY, were screened for polymorphic sites in 53-72 representatives of the five continents. A total of 98 variants were found, yielding nucleotide diversity estimates of 2.45 x 10(-5), 5. 07 x 10(-5), and 8.54 x 10(-5) for the coding regions of SMCY, DFFRY, and UTY1, respectively, with no variant having been observed in DBY. In agreement with most autosomal genes, diversity estimates for the noncoding regions were about 2- to 3-fold higher and ranged from 9. 16 x 10(-5) to 14.2 x 10(-5) for the four genes. Analysis of the frequencies of derived alleles for all four genes showed that they more closely fit the expectation of a Luria-Delbrück distribution than a distribution expected under a constant population size model, providing evidence for exponential population growth. Pairwise nucleotide mismatch distributions date the occurrence of population expansion to approximately 28,000 years ago. This estimate is in accord with the spread of Aurignacian technology and the disappearance of the Neanderthals.     

A novel triphenylacrylonitrile based AIEgen for high contrast mechanchromism and bicolor electroluminescence

A novel thermally stable and aggregation-induced emission (AIE) active compound, 2,2''-(([1,1′-biphenyl]-4,4′-diylbis(phenylazanediyl))bis(4,1-phenylene))bis(3,3-diphenylacrylonitrile) (BP2TPAN) was synthesized through a C–N coupling reaction between 2-(4-bromophenyl)-3,3-diphenylacrylonitrile (Br-TPAN) and N,N′-diphenyl-1,4-phenylenediamine, under mild conditions using Pd(OAc)₂ and P(t-Bu)₃ as a catalyst. The BP2TPAN was characterized by nuclear magnetic resonance spectroscopy, high resolution mass spectrometry and elemental analysis. The thermal analysis showed that the glass transition and decomposition temperatures (5% weight loss) are 96 and 414 °C, respectively. The fluorescent emission peaks changes at 540 and 580 nm upon grinding were attributed to a transformation from crystal to amorphous occurring by altering the condensed state. The photoluminescence quantum yield and fluorescence lifetime of the as prepared and ground samples were 74.3 and 8.4%, 3.4 and 5.1 ns, respectively. The difference of the luminous efficiency of before and after grinding samples indicates BP2TPAN has a high contrast more importantly, both doped and nondoped OLED devices emit different color, the doped one is highly efficient and its L_max, CE_max, PE_max and EQE are up to 15 070 cd m⁻², 11.0 cd A⁻¹, 7.5 lm W⁻¹, and 3.1%, respectively.

An AIE luminogen with high contrast mechanochromic and bicolor electroluminescence.     

Preferential occupancy of Eu3+ and energy transfer in Eu3+ doped Sr2V2O7, Sr9Gd(VO4)7 and Sr2V2O7/Sr9Gd(VO4)7 phosphors

The vanadate-based phosphors Sr₂V₂O₇:Eu³⁺ (SV:Eu³⁺), Sr₉Gd(VO₄)₇:Eu³⁺ (SGV:Eu³⁺) and Sr₉Gd(VO₄)₇/Sr₂V₂O₇:Eu³⁺ (SGV/SV:Eu³⁺) were obtained by solid-state reaction. The bond-energy method was used to investigate the site occupancy preference of Eu³⁺ based on the bond valence model. By comparing the change of bond energy when the Eu³⁺ ions are incorporated into the different Sr, V or Gd sites, we observed that Eu³⁺ doped in SV, SGV or SV/SGV would preferentially occupy the smaller energy variation sites, i.e., Sr4, Gd and Gd sites, respectively. The crystal structures of SGV and SV, the photoluminescence properties of SGV:Eu³⁺, SV, SGV/SV and SGV/SV:Eu, as well as their possible energy transfer mechanisms are proposed. Interesting tunable colours (including warm-white emission) of SGV/SV:Eu³⁺ can be obtained through changing the concentration of Eu³⁺ or changing the relative quantities of SGV to SV by increasing the calcination temperature. Its excitation bands consist of two types of O²⁻ → V⁵⁺ charge transfer (CT) bands with the peaks at about 325 and 350 nm respectively, as well as f–f transitions of Eu³⁺. The obtained warm-white emission consists of a broad photoluminescence band centred at about 530 nm, which originates from the O²⁻ → V⁵⁺ CT of SV, and a sharp characteristic spectrum (⁵D₀–⁷F₂) at about 615 and 621 nm.

The vanadate-based phosphors Sr₂V₂O₇:Eu³⁺ (SV:Eu³⁺), Sr₉Gd(VO₄)₇:Eu³⁺ (SGV:Eu³⁺) and Sr₉Gd(VO₄)₇/Sr₂V₂O₇:Eu³⁺ (SGV/SV:Eu³⁺) were obtained by solid-state reaction.     

High-performance thin H:SiON OLED encapsulation layer deposited by PECVD at low temperature

Highly moisture permeation resistive and transparent single layer thin films for the encapsulation of hydrogenated silicon oxynitrides (H:SiON) were deposited by plasma-enhanced chemical vapor deposition (PECVD) using silane (SiH₄), nitrous oxide (N₂O), ammonia (NH₃), and hydrogen (H₂) at 100 °C for applications to a top-emission organic light-emitting diode (TEOLED). Addition of H₂ into the PECVD process of SiON film deposition afforded the hydrogenated SiON film, which showed not only improved optical properties such as transmittance and reflectance but also better barrier property to water permeation than PECVD SiON and even SiN_x. The H:SiON film with thickness of only 80 nm exhibited water vapor transmission rate (WVTR) lower than 5 × 10⁻⁵ g per m² per day in the test conditions of 38 °C and 100% humidity, where this WVTR is the measurement limit of the MOCON equipment. An additional coating of UV curable polymer enabled the H:SiON films to be flexible and to have very stable barrier property lower than 5 × 10⁻⁵ g per m² per day even after a number of 10k times bending tests at a curvature radius of 1R. The mild H:SiON film process improved the electrical properties of top-emission OLEDs without generating any dark spots. Furthermore, single H:SiON films having high water vapor barrier could maintain the original illumination features of TEOLED longer than 720 hours. These excellent properties of the H:SiON thin films originated from the structural changes of the SiON material by the introduction of hydrogen.

High-performance H:SiON single layer thin film encapsulation (TFE) was deposited by plasma enhanced chemical vapor deposition (PECVD) method. To control the characteristics of the SiON thin films, hydrogen gas was introduced during PECVD process.     

Highly stretchable,mechanically stable,and weavable reduced graphene oxide yarn with high NO2 sensitivity for wearable gas sensors

Stretchable gas sensors are important components of wearable electronic devices used for human safety and healthcare applications. However, the current low stretchability and poor stability of the materials limit their use. Here, we report a highly stretchable, stable, and sensitive NO₂ gas sensor composed of reduced graphene oxide (RGO) sheets and highly elastic commercial yarns. To achieve high stretchability and good stability, the RGO sensors were fabricated using a pre-strain strategy (strain-release assembly). The fabricated stretchable RGO gas sensors showed high NO₂ sensitivity (55% at 5.0 ppm) under 200% strain and outstanding mechanical stability (even up to 5000 cycles at 400% applied strain), making them ideal for wearable electronic applications. In addition, our elastic graphene gas sensors can also be woven into fabrics and clothes for the creation of smart textiles. Finally, we successfully fabricated wearable gas-sensing wrist-bands from superelastic graphene yarns and stretchable knits to demonstrate a wearable electronic device.

Highly stretchable, mechanically stable and weavable RGO elastic electronic yarns were developed using dip-coating with pre-straining. We demonstrate wearable gas sensors that can be worn on the wrist.     

Blood-based immunoassay of tau proteins for early diagnosis of Alzheimer's disease using surface plasmon resonance fiber sensors

We present the immunoassay of tau proteins (total tau and phosphorylated tau) in human sera using surface plasmon resonance (SPR) fiber sensors. This assay aimed at harvesting the advantages of using both SPR fiber sensors and a blood-based assay to demonstrate label-free point-of-care-testing (POCT) patient-friendly assay in a compact format for the early diagnosis of Alzheimer''s disease (AD). For conducting the assay, we used human sera of 40 subjects divided into halves, which were grouped into AD patients and control groups according to a number of neuropsychological tests. We found that on an average, the concentrations of both total tau and phosphorylated tau proteins (all known to be higher in cerebrospinal fluid (CSF) and the brain) turned out to be higher in human sera of AD patients than in controls. The limits of detection of total tau and phosphorylated tau proteins were 2.4 pg mL⁻¹ and 1.6 pg mL⁻¹, respectively. In particular, it was found that the AD group exhibited average concentration of total tau proteins 6-fold higher than the control group, while concentration of phosphorylated tau proteins was 3-fold higher than that of the control. We can attribute this inhomogeneity between both types of tau proteins (in terms of increase of control-to-AD in average concentration) to un-phosphorylated tau proteins being more likely to be produced in blood than phosphorylated tau proteins, which possibly is one of the potential key elements playing an important role in AD progress.

Blood-based early diagnosis of Alzheimer''s disease using a plasmonic fiber sensor that detects immunoreaction of tau proteins.     

Formation mechanism and characterization of porous biomass carbon for excellent performance lithium-ion batteries

Porous biomass carbon derived from corn stalks was prepared via carbonization and activation of CaCl₂. Combined with its microstructure, the formation mechanism and electrochemical properties were analyzed. The addition of CaCl₂ was the key factor to form the porous structure, and the proportion of CaCl₂ had a significant impact on the pores distribution and electrochemical properties. The resulting sample had a specific surface area of 370.6 m² g⁻¹ and an average pore size of 9.65 nm. The sample was circulated at 0.2C for 100 cycles, the specific discharge capacity was 783 mA h g⁻¹. After 60 cycles at different rates, when the current was restored to 0.2C again, the discharge specific capacity quickly recovered. This showed that the sample had excellent rate performance and cycle stability for lithium-ion batteries.

Porous biomass carbon derived from corn stalks was prepared via carbonization and activation of CaCl₂.     

Examining practical nursing experiences to discover ways in which to retain and invigorate the remaining functions of the elderly with a demented and complex disability in nursing homes

Aim

The bedridden elderly with moderate‐to‐severe dementia account for a large proportion of the residents in nursing homes and form a specialized group requiring customized care in order to encourage their remaining functions, which determine the quality of their residual life. The purpose of this study was to search for ways to invigorate and foster the remaining functions of this complex‐disability group, based on practical nursing strategies in nursing homes.

Methods

The qualitative thematic analysis was done by conducting in‐depth interviews with 29 nurses working at 11 different nursing homes in South Korea.

Results

This study proposed four main themes and 19 sub themes as keys for providing specialized nursing care to the elderly with physical and cognitive disabilities. The main themes encourage the residents' remaining functions: (i) accurate identification of an elderly resident's physical, cognitive, and behavioral baseline is necessary in order to determine their functional levels; (ii) nurses provide meticulous management to support the remaining functions in order to prevent further deterioration; (iii) optimized know‐how, based on accumulated experience and knowledge, is reflected in nursing strategies that maximize the effects of nursing interventions; and (iv) steady compliance with nursing guidelines and standards in nursing homes creates the best therapeutic environment and brings unexpected positive changes in the elderly's status.

Conclusion

A practical nursing strategy to target the group with a demented and complex disability in nursing homes was developed through thematic analysis of the empirical knowledge of nurses. The findings provide new insights for developing specialized nursing interventions and practical nursing models in long‐term care facilities.