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In this study, a 355-nm pulsed laser was used to cut 350-μm-thick silicon carbide wafers. The surface morphology and changes in the elemental composition and structure of the cutting line after processing were analyzed using lasers with various laser power, pulse repetition frequency, scanning speed, and scanning repetition settings; they were also compared with those observed for a test piece made using a diamond wheel. An average laser power of 6 W, pulse repetition frequency of 60 kHz, and scanning speed of 5 mm/s minimized oxidation and achieved a groove width of 18.6 μm—15.1 μm narrower than the diamond-cut groove. X-ray photoelectron spectroscopy revealed that the heat-affected zone and the oxygen content of the surface recast layer increased when the laser energy and number of repetitions increased or when the scanning speed decreased. Oxygen content increased from 15.93% (diamond cutting) to up to 47.81%.

This study aims to investigate ultraviolet (UV) laser patterning QR codes on printed circuit boards (PCBs) for the inventory management of image recognition. The developed technology is a green manufacture and can replace the harmful environmental substances of brominated epoxy resin ink for the PCB process. In this study, the recognizability of the laser-patterned QR codes and the relationship between the ablated depth and the color change were investigated. The gray relational analysis (GRA) method was adopted to obtain the optimal laser patterning parameters. Furthermore, a spectrophotometer, scanning electron microscope, laser confocal microscope, and spectrometer were used to examine the light absorbance, the ablated depth, the pattern morphology, and the change in light reflectance of the laser-patterned QR codes on PCBs, respectively. The laser-patterned results revealed that QR codes produced white images with an ablation depth ranging from 5 to 10 μm as the scan speed was 300 mm/s at a laser power of 2 W and the scan speed was 900 mm/s at a laser power of 3—6 W. Moreover, the light reflectance of the white sample was close to 0.3819—0.3139, which was a parameter for successful whitening and was easy to recognize by a smartphone app. According to GRA results, the recognized QR code image could be patterned by the parameters of 2 W laser power, 300 mm/s scan speed, and 60 μm scan space. Furthermore, the scan speed was a severe impact factor for laser-patterned QR codes.

Laser-patterned small-scale QR codes have been widely used for rapid product identification in production history or inventory management. This study proposed a laser-heating oxidation mechanism to produce highly recognizable QR codes on metal surfaces that could save processing time and prevent environmental damage caused by chemical printing. Hence, maskless ultraviolet lasers with a wavelength of 355 nm were used to irradiate on the surface of alloys SS316 and Ti-64. The laser-patterned surface generated an oxide layer without ablating materials and produced the color change between oxides and raw materials. Laser power, scan speed, and scan spacing were adjusted to pattern QR codes for product identification. The tested results demonstrated that a higher laser power, slower scan speed, and lower scan spacing produced a dark oxide layer. This was due to a phenomenon of high thermal accumulation. Furthermore, the image recognition by the smartphone was more stable when the QR code was patterned with a scan speed of 60 mm/s and a scan spacing of 40 μm. The patterned QR codes for Ti-64 have significantly black colors compared to those for SS316. QR codes on surfaces SS316 and Ti-64 were found to have the ability to be recognized since the laser areal fluence was greater than 156.3 J/cm 2 . The elemental oxygen content of SS316 and Ti-64 treated with 625 J/cm 2 was greater than 3.5 and 50.8 times compared to the untreated, respectively. The grain size of SS316 and Ti-64 before and after maskless laser patterning does not have a significant change in the lattice structure. The proposed approach can be widely applied in IoTs for manufacturing components that need to use QR codes in conjunction with the barcode reader to quickly manage inventory.

Nanoimprint lithography (NIL) is a useful technique for the fabrication of nano/micro-structured materials. This article reviews NIL in the field of demolding processes and is divided into four parts. The first part introduces the NIL technologies for pattern replication with polymer resists (e.g., thermal and UV-NIL). The second part reviews the process simulation during resist filling and demolding. The third and fourth parts discuss in detail the difficulties in demolding, particularly interfacial forces between mold (template) and resist, during NIL which limit its capability for practical commercial applications. The origins of large demolding forces (adhesion and friction forces), such as differences in the thermal expansion coefficients (CTEs) between the template and the imprinted resist, or volumetric shrinkage of the UV-curable polymer during curing, are also illustrated accordingly. The plausible solutions for easing interfacial interactions and optimizing demolding procedures, including exploring new resist materials, employing imprint mold surface modifications (e.g., ALD-assisted conformal layer covering imprint mold), and finetuning NIL process conditions, are presented. These approaches effectively reduce the interfacial demolding forces and thus lead to a lower defect rate of pattern transfer. The objective of this review is to provide insights to alleviate difficulties in demolding and to meet the stringent requirements regarding defect control for industrial manufacturing while at the same time maximizing the throughput of the nanoimprint technique.

Background Habenaria species typically produce green or white flowers, bear nectar spurs, emit crepuscular-nocturnal scents, and are usually pollinated by crepuscular/nocturnal moths. However, the roles of floral traits in pollinator differentiation contributing to reproductive success in sympatric Habenaria species require further definition. In this study, we investigated flowering phenology, floral traits, pollinator behavior, and reproductive success of two co-occurring and co-blooming Habenaria species ( H. ciliolaris and H. schindleri ) in southeastern China. We also conducted intraspecific and interspecific hand pollinations to determine their respective breeding systems and the extent of interspecific post-pollination isolation. Results Both species are self-compatible but rely on pollinators for sexual reproduction. Habenaria ciliolaris was pollinated by two species of nocturnal, settling moths ( Thinopteryx nebulosa and Porsica sp.). They foraged for nectar upside down or from one side, carrying pollinaria on their eyes because the curved lateral lobes of the labellum block the movements of settling moths on these flowers. Habenaria schindleri was pollinated by two crepuscular hawkmoths ( Eupanacra mydon and Hippotion rafflesi ), which carried pollinaria between their palpi while hovering in front of flowers while taking nectar. The proboscis lengths of pollinators of both Habenaria species matched the spur lengths of their corresponding flowers. Habenaria ciliolaris experienced a high level of inbreeding depression. Interspecific pollination by applying pollen grains from H. schindleri to the stigmas of H. ciliolaris , resulted in a low level of seed set. Conclusions Differences in floral morphology and nectar volume/concentration appear to contribute to segregating members of the pollinator guild of some Habenaria species. These findings offer new insights to our understanding of the partitioning of pollinators between co-blooming congeners in the Orchidaceae.

The current research tried to explore the effect of Qiweibaizhu powder (QWBZP) on the bacterial diversity and community structure of the intestinal mucosa of dysbiosis diarrhea mice and provide a scientific basis for the efficacy of QWBZP on antibiotic-induced diarrhea. A dysbiosis diarrhea mouse model was constructed with broad-spectrum antibiotics through a mixture of cephradine capsules and gentamicin sulfate (23.33 mL·kg-1·d-1). Intestinal mucosa was collected, and DNA was extracted from each group. The bacterial characteristics in intestinal mucosa were analyzed by MiSeq sequencing based on the 16S rRNA sequencing platform. There were no significant differences in alpha diversity indices among the three groups. The sample distributions in both the normal and QWBZP groups were relatively concentrated, and the distance among individuals was close. However, an opposite result was obtained in the model group. Furthermore, the composition and abundance of species were similar between the normal group and the QWBZP group at both the phylum and genus levels. After treatment with QWBZP, the abundance of Lactobacillus increased, and Proteobacteria decreased, and the Firmicutes/Bacteroidetes ratio decreased to a normal level. Our results indicate that QWBZP can help repair mucosal bacterial structure and recover mucosal microbiota. Specifically, QWBZP increased the abundance of Lactobacillus and Bacteroidales S24-7 group norank.

Background Prostate cancer is the second most common cancer in men, and some new target genes are needed to predict the risk of prostate cancer progression and the treatment. Methods In this study, the effects of UAP1L1 (UAP1-like-1) on prostate cancer were investigated by detecting the proliferation, migration, invasion and apoptosis of prostate cancer cells in vitro using MTT, wound healing, Transwell and flow cytometry assay, and the tumor growth in vivo. The downstream genes and pathways of UAP1L1 were explored using Ingenuity Pathway Analysis (IPA), and screened by qRT-PCR and western blot. The effects of CDCA8 on prostate cancer cells were also verified in vitro, which was through detecting the change of proliferation, migration, invasion and apoptosis of prostate cancer cells after CDCA8 knockdown. Results The results indicated that UAP1L1 promoted the proliferation, migration and invasion of prostate cancer cells, which was inhibited by downregulating CDCA8. Furthermore, the promotion of CDCA8 knockdown on cell apoptosis was reduced when UAP1L1 was simultaneously overexpressed. Conclusions In conclusion, the results in this study revealed that UAP1L1 promoted the progression of prostate cancer through the downstream gene CDCA8.

Background MicroRNAs (miRNAs) are involved in cancer development and progression, acting as tumor suppressors or oncogenes. Our previous studies have revealed that miR-148a and miR-152 are significantly down-regulated in gastrointestinal cancers. Interestingly, miR-148b has the same \"seed sequences\" as miR-148a and miR-152. Although aberrant expression of miR-148b has been observed in several types of cancer, its pathophysiologic role and relevance to tumorigenesis are still largely unknown. The purpose of this study was to elucidate the molecular mechanisms by which miR-148b acts as a tumor suppressor in gastric cancer. Results We showed significant down-regulation of miR-148b in 106 gastric cancer tissues and four gastric cancer cell lines, compared with their non-tumor counterparts by real-time RT-PCR. In situ hybridization of ten cases confirmed an overt decrease in the level of miR-148b in gastric cancer tissues. Moreover, the expression of miR-148b was demonstrated to be associated with tumor size (P = 0.027) by a Mann-Whitney U test. We also found that miR-148b could inhibit cell proliferation in vitro by MTT assay, growth curves and an anchorage-independent growth assay in MGC-803, SGC-7901, BGC-823 and AGS cells. An experiment in nude mice revealed that miR-148b could suppress tumorigenicity in vivo . Using a luciferase activity assay and western blot, CCKBR was identified as a target of miR-148b in cells. Moreover, an obvious inverse correlation was observed between the expression of CCKBR protein and miR-148b in 49 pairs of tissues (P = 0.002, Spearman's correlation). Conclusions These findings provide important evidence that miR-148b targets CCKBR and is significant in suppressing gastric cancer cell growth. Maybe miR-148b would become a potential biomarker and therapeutic target against gastric cancer.

A typical characteristics of polydnavirus (PDV) infection is a persistent immunosuppression, governed by the viral integration and expression of virulence genes. Recently, activation of caspase-3 by Microplitis bicoloratus bracovirus (MbBV) to cleave Innexins, gap junction proteins, has been highlighted, further promoting apoptotic cell disassembly and apoptotic body (AB) formation. However, whether ABs play a role in immune suppression remains to be determined. Herein, we show that ABs transmitted immunosuppressive signaling, causing recipient cells to undergo apoptosis and dismigration. Furthermore, the insertion of viral–host integrated motif sites damaged the host genome, stimulating eIF5A nucleocytoplasmic transport and activating the eIF5A-hypusination translation pathway. This pathway specifically translates apoptosis-related host proteins, such as P53, CypA, CypD, and CypJ, to drive cellular apoptosis owing to broken dsDNA. Furthermore, translated viral proteins, such Vank86, 92, and 101, known to complex with transcription factor Dip3, positively regulated DHYS and DOHH transcription maintaining the activation of the eIF5A-hypusination. Mechanistically, MbBV-mediated extracellular vesicles contained inserted viral fragments that re-integrated into recipients, potentially via the homologous recombinant repair system. Meanwhile, this stimulation regulated activated caspase-3 levels via PI3K/AKT 308 and 473 dephosphorylation to promote apoptosis of granulocyte-like recipients Sf9 cell; maintaining PI3K/AKT 473 phosphorylation and 308 dephosphorylation inhibited caspase-3 activation leading to dismigration of plasmatocyte-like recipient High Five cells. Together, our results suggest that integration-mediated eIF5A hypusination drives extracellular vesicles for continuous immunosuppression.

Skin and mucosa detachment is a symptom of toxic epidermal necrolysis (TEN), a severe cutaneous adverse reaction with a high mortality and infection rates. Toxic epidermal necrolysis disease's associated variables and treatment approaches have been the subject of several investigations in recent years; nonetheless, the causes and treatment approaches of TEN remain unclear. With the goal of provide new insights and approaches for the prevention and management of toxic epidermal necrolysis, this study examines the epidemiology, associated risk factors, and advancements in therapy.