Survival Motor Neuron Protein Participates in Mouse Germ Cell Development and Spermatogonium Maintenance.

The defective human survival motor neuron 1 (SMN1) gene leads to spinal muscular atrophy (SMA), the most common genetic cause of infant mortality. We previously reported that loss of SMN results in rapid differentiation of Drosophila germline stem cells and mouse embryonic stem cells (ESCs), indicating that SMN also plays important roles in germ cell development and stem cell biology. Here, we show that in healthy mice, SMN is highly expressed in the gonadal tissues, prepubertal spermatogonia, and adult spermatocytes, whereas low SMN expression is found in differentiated spermatid and sperm. In SMA-like mice, the growth of testis tissues is retarded, accompanied with gamete development abnormalities and loss of the spermatogonia-specific marker. Consistently, knockdown of Smn1 in spermatogonial stem cells (SSCs) leads to a compromised regeneration capacity in vitro and in vivo in transplantation experiments. In SMA-like mice, apoptosis and accumulation of the R-loop structure were significantly elevated, indicating that SMN plays a critical role in the survival of male germ cells. The present work demonstrates that SMN, in addition to its critical roles in neuronal development, participates in mouse germ cell and spermatogonium maintenance.

Effects of home-based long-term care services on caregiver health according to age.

BACKGROUND: Caregiver health is a crucial public health concern due to the increasing number of elderly people with disabilities. Elderly caregivers are more likely to have poorer health and be a care recipient than younger caregivers. The Taiwan government offers home-based long-term care (LTC) services to provide formal care and decrease the burden of caregivers. This study examined the effects of home-based LTC services on caregiver health according to caregiver age. METHODS: This cross-sectional study included a simple random sample of care recipients and their caregivers. The care recipients had used LTC services under the Ten-Year Long-Term Care Project (TLTCP) in Taiwan. Data were collected through self-administered questionnaires from September 2012 to January 2013. The following variables were assessed for caregivers: health, sex, marital status, education level, relationship with care recipient, quality of relationship with care recipient, job, household monthly income, family income spent on caring for the care recipient (%) and caregiving period. Furthermore, the following factors were assessed for care recipients: age, sex, marital status, education level, living alone, number of family members living with the care recipient, quality of relationship with family and dependency level. The health of the caregivers and care recipients was measured using a self-rated question (self-rated health [SRH] was rated as very poor, poor, fair, good and very good). RESULTS: The study revealed that home nursing care was significantly associated with the health of caregivers aged 65 years or older; however, caregivers aged less than 65 who had used home nursing care, rehabilitation or respite care had poorer health than those who had not used these services. In addition, the following variables significantly improved the health of caregivers aged 65 years or older: caregiver employment, 20% or less of family income spent on caregiving than 81%-100% and higher care recipient health. The involvement of daughters-in-law, rather than spouses, and care recipient health were positively related to the health of caregivers aged less than 65 years. CONCLUSIONS: The findings suggest that home-based LTC service use benefits the health of elderly caregivers. By contrast, home-based LTC service use may be negatively correlated with the health of the caregivers aged less than 65 years.

Cesium Modulation in Cu(In, Ga)(S, Se)2 Solar Cells: Comprehensive Analysis on Interface, Surface, and Grain Boundary.

Cesium (Cs) incorporation and sulfurization on copper indium gallium selenide solar cells are the keys to improving the device quality. In this study, we explore the impact of Cs modulation on sulfur-containing Cu(In, Ga)(S, Se)2 (CIGSSe) absorbers, resulting in a performance increase of over 2%, reaching 18.11%. The improvement stems from a widened surface bandgap, grain boundary (GB) passivation, and a moderate injection blocking layer. The surface bandgap widens from 1.44 to 2.63 eV after Cs incorporation, confirmed by ultraviolet photoelectron spectroscopy (UPS) and low-energy inverse photoemission spectroscopy (LEIPS) analysis. Cs presence and S depletion in GBs suggest a new phase that might mitigate carrier recombination. Heightened Cs incorporation introduces interface issues, including an augmented injection blocking layer and interface defects. Our study offers insights into interface challenges and GB engineering strategies in Cs-treated CIGSSe solar cells, illuminating the multifaceted impact of heavy alkali metal ion Cs in CIGS-based photovoltaics.

Ginkgolide A improves the pleiotropic function and reinforces the neuroprotective effects by mesenchymal stem cell-derived exosomes in 6-OHDA-induced cell model of Parkinson's disease.

Parkinson's disease (PD) is a common disorder attributed to the loss of midbrain dopamine (mDA) neurons and reduced dopamine secretion. Currently, the treatment regimes for PD comprise deep brain stimulations, however, it attenuates the PD progression marginally and does not improve neuronal cell death. We investigated the function of Ginkgolide A (GA) to reinforce Wharton's Jelly-derived mesenchymal stem cells (WJMSCs) for treating the in vitro model of PD. GA enhanced the self-renewal, proliferation, and cell homing function of WJMSCs as assessed by MTT and transwell co-culture assay with a neuroblastoma cell line. GA pre-treated WJMSCs can restore 6-hydroxydopamine (6-OHDA)-induced cell death in a co-culture assay. Furthermore, exosomes isolated from GA pre-treated WJMSCs significantly rescued 6-OHDA-induced cell death as determined by MTT assay, flow cytometry, and TUNEL assay. Western blotting showed that apoptosis-related proteins were decreased following GA-WJMSCs exosomal treatment which further improved mitochondrial dysfunction. We further demonstrated that exosomes isolated from GA-WJMSCs could restore autophagy using immunofluorescence staining and immunoblotting assay. Finally, we used the alpha-synuclein recombinant protein and found that exosomes derived from GA-WJMSCs led to the reduced aggregation of alpha-synuclein compared to that in control. Our results suggested that GA could be a potential candidate for strengthening stem cell and exosome therapy for PD.

Survival Motor Neuron Enhances Pluripotent Gene Expression and Facilitates Cell Reprogramming.

Survival motor neuron (SMN) plays important roles in snRNP assembly and mRNA splicing. Deficiency of SMN causes spinal muscular atrophy (SMA), a leading genetic disease causing childhood mortality. Previous studies have shown that SMN regulates stem cell self-renewal and pluripotency in Drosophila and mouse and is abundantly expressed in mouse embryonic stem cells. However, whether SMN is required for establishment of pluripotency is unclear. In this study, we show that SMN is gradually upregulated in preimplantation mouse embryos and cultured cells undergoing cell reprogramming. Ectopic expression of SMN increased cell reprogramming efficiency, whereas knockdown of SMN impeded induced pluripotent stem cell (iPSC) colony formation. iPSCs could be derived from SMA model mice, but impairment in differentiation capacity may be present. The ectopic overexpression of SMN in iPSCs can upregulate the expression levels of some pluripotent genes and restore the neuronal differentiation capacity of SMA-iPSCs. Taken together, our findings not only demonstrate the functional relevance of SMN in establishment of cell pluripotency but also propose its potential application in facilitating iPSC derivation.

In-Situ observation of local atomic structure of Al-Cu-Fe quasicrystal formation.

The phase and local environment, neighbouring atoms and coordination numbers (CN), for an Al-Cu-Fe multilayer were studied during heating (to 800 °C) and cooling (to room temperature) processes using in-situ X-Ray diffraction (XRD) and in-situ X-ray absorption spectroscopy (XAS) techniques to investigate the formation of Al-Cu-Fe quasicrystals (QCs). In-situ XRD clarified the transition of the ω-Al7Cu2Fe phase to a liquid state at the high temperature which transformed into the QC phase during cooling. The in-situ XAS showed a relatively small shift in distance between Cu-Al and Fe-Al during the phase evolution from RT to 700 °C. The distance between Cu-Cu, however, showed a significant increase from ω-phase at 700 °C to the liquid state at 800 °C, and this distance was maintained after QC formation. Furthermore, the CN of Fe-Al was changed to N = 9 during cooling. Through our observations of changes in CN, atomic distances and the atomic environment, we propose the local structural ordering of the quasicrystalline phase originated from a liquid state via ω-phase. In this study, we give a clear picture of the atomic environment from the crystalline to the quasicrystalline phase during the phase transitions, which provides a better understanding of the synthesis of functional QC nanomaterials.

Ni-Al-Cr superalloy as high temperature cathode current collector for advanced thin film Li batteries.

To obtain full advantage of state-of-the-art solid-state lithium-based batteries, produced by sequential deposition of high voltage cathodes and promising oxide-based electrolytes, the current collector must withstand high temperatures (>600 °C) in oxygen atmosphere. This imposes severe restrictions on the choice of materials for the first layer, usually the cathode current collector. It not only must be electrochemically stable at high voltage, but also remain conductive upon deposition and annealing of the subsequent layers without presenting a strong diffusion of its constituent elements into the cathode. A novel cathode current collector based on a Ni-Al-Cr superalloy with target composition Ni0.72Al0.18Cr0.10 is presented here. The suitability of this superalloy as a high voltage current collector was verified by determining its electrochemical stability at high voltage by crystallizing and cycling of LiCoO2 directly onto it.

Room-Temperature Chemical Solution Treatment for Flexible ZnS(O,OH)/Cu(In,Ga)Se2 Solar Cell: Improvements in Interface Properties and Metastability.

We demonstrate an effective room-temperature chemical solution treatment, by using thioacetamide (S treatment) or thioacetamide-InCl3 (In-S treatment) solution, on Cu(In,Ga)Se2 (CIGSe) surface to engineer the ZnS(O,OH)/CIGSe interface and junction quality, leading to enhanced efficiency and minimized metastability of flexible solar cells. The control device without treatment reveals a relatively low efficiency of 8.15%, which is significantly improved to 9.74% by In-S treatment, and 10.39% by S treatment. Results of X-ray photoelectron spectroscopy suggest that S is incorporated into CIGSe surface forming CIGSSe by S treatment, whereas a thin In-S layer is formed on CIGSe surface by In-S treatment with reduced amount of S diffusing into CIGSe. PL spectra and TRPL lifetime further reveal that S incorporation into CIGS surface may substitute the OSe and/or directly occupy the vacant anion site (VSe), resulting in the effective passivation of the recombination centers at CIGSe surface. Moreover, reducing the concentrations of VSe may thereby decrease the density of (VCu-VSe) acceptors, which can minimize the metastability of ZnS(O,OH)/CIGSe solar cells. With S treatment, the light soaking (LS) time of ZnS(O,OH)/CIGSe device is reduced approximately to one-half of control one. Our approach can be potentially applied for alternative Cd-free buffer layers to achieve high efficiency and low metastability.

Thermal dewetting with a chemically heterogeneous nano-template for self-assembled L1(0) FePt nanoparticle arrays.

A design for the fabrication of metallic nanoparticles is presented by thermal dewetting with a chemically heterogeneous nano-template. For the template, we fabricate a nanostructured polystyrene-b-polydimethylsiloxane (PS-b-PDMS) film on a Si|SiO2 substrate, followed by a thermal annealing and reactive ion etching (RIE) process. This gives a template composed of an ordered hexagonal array of SiOC hemispheres emerging in the polystyrene matrix. After the deposition of a FePt film on this template, we utilize the rapid thermal annealing (RTA) process, which provides in-plane stress, to achieve thermal dewetting and structural ordering of FePt simultaneously. Since the template is composed of different composition surfaces with periodically varied morphologies, it offers more tuning knobs to manipulate the nanostructures. We show that both the decrease in the area of the PS matrix and the increase in the strain energy relaxation transfer the dewetted pattern from the randomly distributed nanoparticles into a hexagonal periodic array of L10 FePt nanoparticles. Transmission electron microscopy with the in situ heating stage reveals the evolution of the dewetting process, and confirms that the positions of nanoparticles are aligned with those of the SiOC hemispheres. The nanoparticles formed by this template-dewetting show an average diameter and center-to-center distance of 19.30 ± 2.09 nm and 39.85 ± 4.80 nm, respectively. The hexagonal array of FePt nanoparticles reveals a large coercivity of 1.5 T, much larger than the nanoparticles fabricated by top-down approaches. This approach offers an efficient pathway toward self-assembled nanostructures in a wide range of material systems.