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Selfish genetic elements (SGEs) increase their transmission efficiency relative to the rest of the individual genome, which is often deleterious to individual fitness. Theoretical studies have suggested that intragenomic conflict over the sex ratio distortion between SGEs and the rest of the genome should lead to the evolution of sex-determining systems. However, in insects, there are relatively few studies other than those on Dipterans, which makes it difficult to understand the role of SGEs in the evolution of insect sex determination. This is partially due to the difficulties in observing SGEs under field conditions. The effect of SGEs is often masked by the counter-evolution of the resistance genes. Interpopulation cross-breeding experiments are effective to detect the SGEs and their resistance genes. If these populations have different SGEs and resistance genes, cross-breeding experiments reveal their existence by collapsing the evolutionary antagonistic state. The Ryukyu drywood termites Neotermes sugioi, distributed in the Ryukyu Islands, show male-biased sex ratios in pseudergates, nymphs, alates and soldiers both in Okinawa and Ishigaki Islands, but different degrees of bias have been reported between the islands. Male-specific microsatellite alleles have been reported in this species, which allowed us to identify the sex of the eggs and young larvae. In this study, we used the microsatellite locus with male-specific alleles to investigate the primary sex ratio of field colonies on Okinawa and Ishigaki islands and the sex ratio of offspring obtained through cross-breeding experiments between the islands. The primary sex ratios of field colonies were male-biased in Okinawa but not in Ishigaki. Cross-breeding experiments showed that Okinawa males tend to have a male-biased sex ratio in their offspring, but Ishigaki males do not. This result is consistent with the hypothesis that the male bias in this species is caused by SGEs, even though termites are phylogenetically distant from Diptera. Accumulation of knowledge on genetic conflicts in a wide range of taxa might be an important step toward elucidating the mechanisms of diversification of sex determination systems in insects.

Abstract Sex‐determination systems often show remarkable diversity in upstream signals, although downstream genes are broadly conserved. Therefore, the downstream genes have been investigated in various taxa, but the most upstream signals determining sex in insects have been well‐described mainly in model organisms, including fruit flies and honey bees, and not in hemimetabolous insects such as termites. Identification of sex‐linked genetic markers in termites is important to the survey of primary sex‐determination signals. Here, we report male‐specific alleles at the microsatellite locus NK12‐1 in the Ryukyu drywood termite Neotermes sugioi (Kalotermitidae). This study provides the third example of a genetic marker linked with sexual phenotype in termites, which is a small but important step to elucidate the evolutionary process of the sex‐determination system in termites.

In most lower termites, colonies are headed by neotenic reproductives of both sexes after the primary reproductives (i.e., the queen and king) are lost. The production of a neotenic sexual is inhibited by the presence of a primary reproductive of the same sex. We found an exception in the caste system of the dry wood termite Neotermes koshunensis (Kalotermitidae). The neotenic caste is exclusively male. Moreover, production of male neotenics is completely inhibited not only by the presence of a king but also by the presence of a queen. Therefore, it is likely to be difficult for N. koshunensis colonies to recover their reproductive pairs.

Introduction: This report describes a case of necrotizing scleritis caused by Pseudomonas aeruginosa infection soon after vitreous surgery, which caused severe scleral melting and rapidly progressive necrosis that led to scleral perforation and bacterial endophthalmitis. Case Presentation: The patient was an 86-year-old man with a history of type 2 diabetes mellitus who underwent pars plana vitrectomy (PPV) for vitreous hemorrhage in his right eye. On postoperative day 10, he complained of severe ocular pain and was found to have conjunctival edema and eyelid swelling, which was treated by topical and general systemic antibiotics. His ocular symptoms improved but subsequently worsened. On postoperative day 25, hypopyon and a fibrinous exudative membrane were observed in the anterior chamber, and the fundus could not be visualized. PPV was repeated with addition of silicone oil tamponade. During the surgery, the retina was found to be completely detached with severe anterior scleral melting, perforation, and necrosis, as well as abscess formation. Culture of an eye discharge specimen detected P. aeruginosa. After surgery, antibiotics were administered and the eye was washed with polyvinyl alcohol-iodine solution daily. Ten days later, the eye pain and eyelid swelling were significantly improved. The scleral inflammation gradually resolved without recurrence. Conclusion: In this case, rapidly progressive necrotizing scleritis caused by P. aeruginosa infection was controlled by a combination of antibiotics, removal of necrotic tissue, and daily eye washing with polyvinyl alcohol-iodine solution.

GHz burst-mode femtosecond (fs) laser, which emits a series of pulse trains with extremely short intervals of several hundred picoseconds, provides distinct characteristics in materials processing as compared with the conventional irradiation scheme of fs laser (single-pulse mode). In this paper, we take advantage of the moderate pulse interval of 205 ps (4.88 GHz) in the burst pulse for high-quality and high-efficiency micromachining of single crystalline sapphire by laser induced plasma assisted ablation (LIPAA). Specifically, the preceding pulses in the burst generate plasma by ablation of copper placed behind the sapphire substrate, which interacts with the subsequent pulses to induce ablation at the rear surface of sapphire substrates. As a result, not only the ablation quality but also the ablation efficiency and the fabrication resolution are greatly improved compared to the other schemes including single-pulse mode fs laser direct ablation, single-pulse mode fs-LIPAA, and nanosecond-LIPAA.

Advanced nucleic acid amplification techniques require separating test samples into numerous units (digitalization), which enables higher sensitivity and accuracy than traditional methods. Reagent partition tools are commercially available, but are usually complex and expensive, hindering mass adoption. Herein, the fabrication of a large‐scale micro‐through‐hole array on glass substrates for an advanced digital nucleic acid amplification technique (NAAT) is demonstrated. To meet the requirement of hole quantities (over tens of thousands) for valid nucleic acid statistics, ultrafast Bessel pulses with continuous translation of the glass substrate are applied. A single‐shot Bessel pulse can lead to a single hole, and 100 holes can be produced per second (scalable to thousands per second). Experiments using the fabricated chips show that the performance meets the NAAT requirements. This work provides a highly efficient and low‐cost scheme for reagent partitioning that promotes the wide accessibility of advanced digital NAATs as well as a variety of other applications.

GHz burst mode femtosecond (fs) laser pulses, which consist of a series of pulse trains with ultra-fast intervals of several hundred picoseconds, have offered distinct features for material processing compared to conventional irradiation of laser pulses (single-pulse mode). We apply GHz burst mode processing to fabricate laser-induced periodic surface structures (LIPSS) on the material surfaces. In our previous work for silicon (Si), we have found that GHz burst mode can create unique two-dimensional (2D) LIPSS composed of both parallel and perpendicular to the laser polarization direction. We proposed that the formation of 2D-LIPSS is attributed to the synergetic contributions of electromagnetic and hydrodynamic mechanisms. To further investigate more detailed formation mechanisms and explore practical applications, we employ titanium (Ti), whose properties are significantly different from Si. We demonstrate that GHz burst mode fs laser pulses (central wavelength: 1,030 nm, intra-pulse width: 230 fs, intra-pulse repetition rate (an intra-pulse interval): 4.88 GHz (205 ps) and burst pulse repetition rate: 10 kHz) can also fabricate 2D-LIPSS on Ti surfaces. We attribute the dominant formation mechanism of 2D-LIPSS to the generation of hot spots with highly enhanced electric fields due to transient change of material properties during GHz burst pulse irradiation. Based on this speculation, properly tailoring the shapes of the burst pulse with an optimum intra-pulse number enables the creation of well-defined 2D-LIPSS. Furthermore, essentially homogeneous 2D-LIPSS can be formed in a large area by laser scanning of a focused fs laser beam with a stage scanning speed of 5 mm/s.

Femtosecond laser direct write (fs-LDW), a three-dimensional (3D) printing technology, is a promising method for creating microstructures made of proteins that retain their original function, enabling the development of complex biomimetic 3D microenvironments and versatile enhancements of medical microdevices. Fabrication using pure proteins via photoactivator-free femtosecond laser multiphoton crosslinking has recently been demonstrated This approach avoids the undesirable effects caused by the leaching of photoactivator molecules, and is thus regarded as suitable for biological applications. Here, we present the 3D fabrication of microstructures made of pure fluorescent protein variants, namely mScarlet, enhanced green fluorescent protein (EGFP), and enhanced blue fluorescent protein (EBFP2). Multicolor fluorescent microstructures are created using a sequential procedure with various precursors. We evaluate the dependence of fluorescence retention on fabrication parameters such as the total accumulated fluence. We demonstrate that microstructures made of EGFP can be applied to the detection of physiological pH changes. The results show that fs-LDW fabrication can broaden the application scope of fluorescent protein variants.

Surface-enhanced Raman scattering (SERS), owing to its high sensitivity based on localized surface plasmon resonance of nanostructured metals, is recently attracting much attention to be used for biotechnology, such as cell imaging and tumor therapy. On the other hand, the trace detection of bio-molecules with large molecular weight is still challenging because the troublesome treatment of SERS substrate using coupling or cross-linking agents is required. In this paper, we apply liquid interface assisted SERS (LI-SERS) method, which provides unique features of collection and self-immobilization of analyte molecules on the SERS substrate, to realize the label-free trace detection of bio-molecules with detection limits of pM ~ fM. Specifically, deoxyribonucleic acid (DNA) discrimination and quantitative detection of β-Amyloid (Aβ) in trace-concentration are demonstrated to illustrate the ultrahigh sensitivity and versatility of the LI-SERS method. The results suggest LI-SERS is promising for the early-stage diagnosis of diseases such as virus infection and Alzheimer's disease.

Orientations of laser induced periodic surface structures (LIPSS) are usually considered to be governed by the laser polarization state. In this work, we unveil that fluid dynamics induced by femtosecond (fs) laser ablation in liquid (fs-LAL) can easily break this polarization restriction to produce irregular circular-LIPSS (CLIPPS) and crisscross-LIPSS (CCLIPSS). Fs laser ablation of silicon in water shows formation of diverse LIPSS depending on ablation conditions. At a high power of 700 mW (repetition rate of 100 kHz, pulse duration of 457 fs and wavelength of 1045 nm), single/twin CLIPSS are produced at the bottom of macropores of several microns in diameter due to the formation of strong liquid vortexes and occurrence of the vortex shedding effect. Theoretical simulations validate our speculation about the formation of liquid vortex with an ultrahigh static pressure, which can induce the microstructure trenches and cracks at the sidewalls for fs-LAL of Si and tungsten (W) in water, respectively. At a low power of 50 mW, weak liquid vortexes are produced, which only give birth to curved LIPSS in the valleys of grooves. Consequently, it is deduced that liquid vortex plays a crucial role in the formation of macropores. Mountain-like microstructures induce complex fluid dynamics which can cause the formation of CCLIPSS on them. It is believed that liquid vortexes and fluid dynamics presented in this work open up new possibilities to diversify the morphologies of LIPSS formed by fs-LAL.

Electrochemical surface‐enhanced Raman scattering (EC‐SERS) is a promising technique for the diagnosis of trace amounts of neurotransmitters, because it can elucidate neurotransmitters’ behavior on electrodes to deduce their functions in the human body. However, the current EC‐SERS devices need several tens of milliliters of analyte solution to collect enough signal for analysis. Miniaturization of EC‐SERS devices is crucial for the early diagnosis of disease and point‐of‐care testing. Herein, a new type of EC‐SERS sensor based on 3D microfluidic chips for the analysis of neurotransmitters in ultrasmall volumes is proposed. The microfluidic EC‐SERS chip is fabricated by a ship‐in‐a‐bottle technique based on hybrid laser processing. The working electrode is modified using silver/zinc oxide materials, enabling the formation of a unique “candy apple” structure. To assess the fabricated microfluidic EC‐SERS chips, ascorbic acid is analyzed using the ingenious microfluidic EC‐SERS chips to elucidate its redox reaction by EC‐SERS spectroscopy. Significantly, a sub‐10 μL volume of analyte solution is sufficient for EC‐SERS analysis, which is several orders smaller in volume than the requirements of current EC‐SERS devices. The unprecedented microfluidic EC‐SERS chips fabricated by the ship‐in‐a‐bottle integration technique can be used in portable and smart analyzers for next‐generation biomedicines and catalysts.

Abstract Background This case report describes the surgical outcome in a patient with congenital X-linked retinoschisis (CXLRS) and the results of proteomic analysis of surgically extracted samples from both vitreous and intraschisis cavities by mass spectrometry. Case presentation A 3-month-old boy presented with extensive retinoschisis involving macula and retinal periphery in both eyes. Genetic analysis confirmed retinoschisin 1 mutation (c.554C > T), and an electroretinogram showed significant reduction of b-wave and decreased cone and rod responses, which led to a diagnosis of CXLRS. By performing pars plana vitrectomy, including inner wall retinectomy, clear visual axes with stable retinal conditions and functional vision in both eyes were obtained during the 4 years of follow-up. Proteomic analysis of surgically retrieved fluid from the intraschisis cavity revealed a higher expression of interphotoreceptor retinoid-binding protein (IRBP) than that from the vitreous humor. However, both samples showed equal levels of albumin, transferrin, and pigment epithelium-derived factor. Conclusions Cellular adhesive imperfection in CXLRS may cause IRBP diffusion from the interphotoreceptor matrix, resulting in the strong expression of IRBP in the intraschisis cavity. An impaired retinoid cycle caused by an absence of IRBP in the retina may potentially underlie the pathology of CXLRS.

Abstract The mechanical strength of hydrogel microstructures is crucial for obtaining the desired flexibility, robustness, and biocompatibility for various applications such as cell scaffolds and soft microrobots. In this study, we demonstrate the fabrication of microstructures composed of cellulose nanofibers (CNFs) and poly(ethylene glycol) diacrylate (PEGDA) hydrogels by multiphoton polymerization. The stress of the fabricated microstructure during tensile testing increased with an increase in the CNF concentration, indicating that the mechanical strength of the microstructure was enhanced by using CNFs as fillers. Moreover, the swelling ratio of the microstructure increased with increasing CNF concentration in the PEGDA hydrogel. Our results show the potential of the technique for the microfabrication of advanced cell scaffolds and soft microrobots with the desired mechanical strength.

Laser-induced near-field effect, which confines the laser energy in a nano scale region to be enhanced, allows the laser fabrication with a resolution much smaller than the wavelength. Owing to such a high fabrication resolution, the laser-induced near-field fabrication has been attracting much attention as a tool for the surface nanostructuring. In this report, we introduce a novel method based on the laser-induced near-field reduction using a femtosecond laser by which gold nanocluster arrays are formed on substrates with the assistance of self-assembled silica microspheres. In the laser near-field reduction, the incident laser is focused in the vicinity of the backside of the silica microspheres to initiate synthesis of gold nanoparticles, followed by creation of gold nanoclusters by continuous growth of the gold nanoparticles along the silica microsphere surfaces. In addition, laser-treated MoS2 quantum dots are mixed in the gold precursor to increase the reduction efficiency for the formation of spherical gold nanoclusters. The gold nanocluster arrays provide potential applications for plasmonic devices.

Femtosecond laser pulses with GHz burst mode that consist of a series of trains of ultrashort laser pulses with a pulse interval of several hundred picoseconds offer distinct features in material processing that cannot be obtained by the conventional irradiation scheme of femtosecond laser pulses (single-pulse mode). However, most studies using the GHz burst mode femtosecond laser pulses focus on ablation of materials to achieve high-efficiency and high-quality material removal. In this study, we explore the ability of the GHz burst mode femtosecond laser processing to form laser-induced periodic surface structures (LIPSS) on silicon. It is well known that the direction of LIPSS formed by the single-pulse mode with linearly polarized laser pulses is typically perpendicular to the laser polarization direction. In contrast, we find that the GHz burst mode femtosecond laser (wavelength: 1030 nm, intra-pulse duration: 220 fs, intra-pulse interval time (intra-pulse repetition rate): 205 ps (4.88 GHz), burst pulse repetition rate: 200 kHz) creates unique two-dimensional (2D) LIPSS. We regard the formation mechanism of 2D LIPSS as the synergetic contribution of the electromagnetic mechanism and the hydrodynamic mechanism. Specifically, generation of hot spots with highly enhanced electric fields by the localized surface plasmon resonance of subsequent pulses in the bursts within the nanogrooves of one-dimensional LIPSS formed by the preceding pulses creates 2D LIPSS. Additionally, hydrodynamic instability including convection flow determines the final structure of 2D LIPSS.

For the practical use of femtosecond laser ablation, inputs of higher laser intensity are preferred to attain high-throughput material removal. However, the use of higher laser intensities for increasing ablation rates can have detrimental effects on ablation quality due to excess heat generation and air ionization. This paper employs ablation using BiBurst femtosecond laser pulses, which consist of multiple bursts (2 and 5 bursts) at a repetition rate of 64 MHz, each containing multiple intra-pulses (2–20 pulses) at an ultrafast repetition rate of 4.88 GHz, to overcome these conflicting conditions. Ablation of silicon substrates using the BiBurst mode with 5 burst pulses and 20 intra-pulses successfully prevents air breakdown at packet energies higher than the pulse energy inducing the air ionization by the conventional femtosecond laser pulse irradiation (single-pulse mode). As a result, ablation speed can be enhanced by a factor of 23 without deteriorating the ablation quality compared to that by the single-pulse mode ablation under the conditions where the air ionization is avoided.

Surface-enhanced Raman scattering (SERS) enables trace-detection for biosensing and environmental monitoring. Optimized enhancement of SERS can be achieved when the energy of the localized surface plasmon resonance (LSPR) is close to the energy of the Raman excitation wavelength. The LSPR can be tuned using a plasmonic superstructure array with controlled periods. In this paper, we develop a new technique based on laser near-field reduction to fabricate a superstructure array, which provides distinct features in the formation of periodic structures with hollow nanoclusters and flexible control of the LSPR in fewer steps than current techniques. Fabrication involves irradiation of a continuous wave laser or femtosecond laser onto a monolayer of self-assembled silica microspheres to grow silver nanoparticles along the silica microsphere surfaces by laser near-field reduction. The LSPR of superstructure array can be flexibly tuned to match the Raman excitation wavelengths from the visible to the infrared regions using different diameters of silica microspheres. The unique nanostructure formed can contribute to an increase in the sensitivity of SERS sensing. The fabricated superstructure array thus offers superior characteristics for the quantitative analysis of fluorescent perfluorooctanoic acid with a wide detection range from 11 ppb to 400 ppm.

Purpose: To report a case of neurotrophic keratopathy associated with nasopharyngeal carcinoma. Case Report: A 59-year-old man who had been diagnosed with a nasopharyngeal carcinoma was referred to the authors because of visual disturbance and pain in his right eye. Slit-lamp examination revealed a corneal epithelial defect and corneal stromal edema surrounding the epithelial defect area in his right eye. Magnetic resonance imaging showed a mass in his cavernous sinus, which was identified as nasopharyngeal carcinoma (NPC). We diagnosed neurotrophic keratopathy associated with NPC and initiated treatment with preservative-free artificial tears, antibiotic eye drops, fibronectin, a therapeutic contact lens, and amniotic membrane transplantation. However, the persistent corneal epithelial defect was unresponsive to these treatments. Conclusion: Neurotrophic keratopathy secondary to NPC is thought to be rare. We presented a case of neurotrophic keratopathy associated with cavernous sinus metastasis of an NPC. The development of new and more effective treatments for this refractory disease is anticipated.

Abstract Background Graft detachment is a complication of non-Descemet stripping automated endothelial keratoplasty (nDSAEK). We report a case of spontaneous reattachment of an extensively dislocated graft after nDSAEK. Case presentation A 54-year-old male underwent penetrating keratoplasty (PKP) for keratoconus in his left eye in 2001. Following graft opacity due to rejection, a second PKP was implemented in May 2014. The graft was kept in good condition after the reoperation and yet, visual acuity (VA) declined due to cataract. PEA+IOL was then performed in May 2015. Because edema appeared in the graft 6 months after the PEA+IOL, nDSAEK was carried out in May 2016. Although the donor graft well attached immediately after the nDSAEK, the graft was almost completely dislocated 3 h later except a temporal part. Air was reinjected into the anterior chamber on the following day and the detachment was resolved. Despite of the treatment, about 1/5 of the graft remained detached and the detachment deteriorated to 3/4 of the graft 9 days later. Because the patient could not decide whether to undergo another operation immediately, we decided to follow him up first and found that the partially detached graft reattached spontaneously 1 month later during the follow-up. Although the cornea had a mild edema remaining in the superior temporal area, his BCVA improved to 1.0. Three months later, the graft remained in position and the cornea kept its transparency. Conclusions Spontaneous reattachment was observed during the follow-up in a case that had shown a comparatively extensive graft dislocation after nDSAEK.

Purpose. To report a case of corneal perforation, in a patient with a history of herpetic keratitis, during combination chemotherapy including cetuximab. Case. We report the case of a 71-year-old man who was diagnosed with a hypopharyngeal carcinoma and received radiation therapy combined with cetuximab, the epidermal growth factor receptor (EGFR) inhibitor monoclonal antibody. He was referred to us because of ocular hyperemia and corneal perforation in his left eye. In spite of conservative therapy, his corneal perforation was exacerbated, with iris incarceration into the wound site and exposure to the surface of the cornea. He therefore discontinued treatment with the combination chemotherapy and underwent lamellar keratoplasty using a preserved donor cornea. After treatment with cetuximab resumed, there was no recurrence of the corneal perforation. Conclusion. We have presented the first case of cetuximab-related corneal perforation in a patient who had a history of recurrent herpetic keratitis. EGFR inhibitors, such as cetuximab, can induce corneal perforation in cases with a history of herpetic stromal keratitis.

Researches on the topological edge state in the photonic lattice are attracting considerable attention. Here, we report the studies on a particular state for which the topological invariant is undefined. We constructed an anti-parity-time-symmetric photonic lattice by using the perturbation method. Light distributes only in the wide waveguides with equal magnitude for the state with undefined winding numbers. Further studies show that the equal intensity transmission is unaffected except for the defect site. Our work provides a new way to study the topological state and the equally divided light transmission and might be applicable in optical circuits and optical interconnect.

Various material processing techniques have been proposed for fabrication of smart surfaces that can modulate cellular behavior and address specific clinical issues. Among them, laser-based technologies have attracted growing interest due to processing versatility. Latest development of ultrashort pulse lasers with pulse widths from several tens of femtoseconds (fs) to several picoseconds (ps) allows clean microfabrication of a variety of materials at micro- and nanoscale both at surface and in volume. In this study, we addressed the possibility of 3D microfabrication of photosensitive glass (PG) by high repetition rate ps laser-assisted etching (PLAE) to improve the fabrication efficiency for the development of useful tools to be used for specific biological applications. Microfluidic structures fabricated by PLAE should provide the flow aspects, 3D characteristics, and possibility of producing functional structures to achieve the biologically relevant microenvironments. Specifically, the microfluidic structures could induce cellular chemotaxis over extended periods in diffusion-based gradient media. More importantly, the 3D characteristics could reproduce capillaries for in vitro testing of relevant organ models. Single cell trapping and analysis by using the fabricated microfluidic structures are also essential for understanding individual cell behavior within the same population. To this end, this paper demonstrates: (1) generation of 3D structures in glass volume or on surface for fabrication of microfluidic channels, (2) subtractive 3D surface patterning to create patterned molds in a controlled manor for casting polydimethylsiloxane (PDMS) structures and developing single cell microchambers, and (3) designing glass photo-masks to be used for sequel additive patterning of biocompatible nanomaterials with controlled shapes, sizes, and periodicity. Mesenchymal stem cells grown on laser-processed glass surfaces revealed no sign of cytotoxicity, while a collagen thin coating improved cellular adhesion.

In this work, we present the possibility of producing multiscale hierarchical micro/nanostructures by the femtosecond laser ablation of transition metals (i.e., Ta and W) in water and investigate their polarization-dependent reflectance. The hierarchical micro/nanostructures are composed of microscale-grooved, mountain-like and pit-rich structures decorated with hybrid laser-induced periodic surface structures (LIPSSs). The hybrid LIPSSs consist of low/high and ultrahigh spatial frequency LIPSSs (LSFLs/HSFLs and UHSFLs). LSFLs/HSFLs of 400–600 nm in a period are typically oriented perpendicular to the direction of the laser polarization, while UHSFLs (widths: 10–20 nm and periods: 30–50 nm) are oriented perpendicular to the curvatures of LSFLs/HSFLs. On the microstructures with height gradients, the orientations of LSFLs/HSFLs are misaligned by 18°. On the ablated W metasurface, two kinds of UHSFLs are observed. UHSFLs become parallel nanowires in the deep troughs of LSFLs/HSFLs but result in being very chaotic in shallow LSFLs, turning into polygonal nanonetworks. In contrast, chaotic USFLs are not found on the ablated Ta metasurfaces. With the help of Fourier transform infrared spectroscopy, it is found that microgrooves show an obvious polarization-dependent reflectance at wavelengths of 15 and 17.5 μm associated with the direction of the groove, and the integration of microstructures with LSFs/HSFLs/UHSFLs is thus beneficial for enhancing the light absorbance and light trapping in the near-to-mid-infrared (NIR-MIR) range.

Purpose. To report a case of persistent corneal epithelial defect that had occurred after a trigeminal nerve block. Case Presentation. A 75-year-old female had suffered from postherpetic neuralgia for 8 years. She underwent Gasserian ganglion block surgery and noticed declining visual acuity in the right eye on the following day. She presented with severe hyperemia and corneal epithelial defects in the right eye and experienced remarkable reduction of sensitivity in the right cornea. She was diagnosed with neurotrophic keratopathy. Ofloxacin eye ointment and rebamipide ophthalmic suspension ameliorated the corneal epithelial defects but superficial punctate keratopathy, corneal superficial neovascularization, and Descemet’s fold persisted. Although the epithelial defects occasionally recurred, the corneal sensation and epithelial defects, Descemet’s fold, and corneal superficial neovascularization all improved around 5 months after trigeminal nerve block. The HRT II Rostock Cornea Module (RCM) could not detect any corneal subbasal nerve fibers at postoperative 4 months; however, it could detect them at postoperative 6 months. Conclusions. As the nerve block effect wore off, the corneal subbasal nerve fibers slowly regenerated. As the corneal sensation improved, the corneal epithelial defects and superficial neovascularization also improved. The HRT II RCM appeared useful for observing loss and regeneration of the corneal subbasal nerve fibers.

Purpose: To report our findings in an infant with Peters anomaly type II whose retinopathy of prematurity (ROP) was treated with an anti-VEGF agent and surgeries. Case Report: A male infant weighing 548 g was born prematurely at 23 weeks and 1 day with corneal opacity and shallow anterior chambers in both eyes. At the postmenstrual age of 35 weeks and 3 days, the infant was tentatively diagnosed with stage 3 ROP because of a dilated tunica vasculosa lentis and ultrasonographic findings. The boy was treated with bilateral intravitreal injections of bevacizumab (IVB) because laser photocoagulation of the retina could not be performed due to the corneal opacity. The retina in the right eye detached 3 times, namely 5 days, 16 days, and 7 months after the IVB; encircling the scleral buckle and a vitrectomy with endolaser photocoagulation were therefore required. In his left eye, the retina was reattached after the initial IVB, and no additional treatment was required. ROP was not reactivated in both eyes until the last examination at the age of 2 years and 6 months. Conclusions: Our results showed that IVB is a useful treatment for ROP in patients with Peters anomaly. However, a retinal detachment can be a complication after IVB. The optimal timing of IVB for ROP in infants with hazy media needs to be determined.

Femtosecond lasers have revolutionized the processing of materials, since their ultrashort pulse width and extremely high peak intensity allows high-quality micro- and nanofabrication of three-dimensional (3D) structures. This unique capability opens up a new route for fabrication of microfluidic sensors for biochemical applications. The present paper presents a comprehensive review of recent advancements in femtosecond laser processing of glass for a variety of microfluidic sensor applications. These include 3D integration of micro-/nanofluidic, optofluidic, electrofluidic, surface-enhanced Raman-scattering devices, in addition to fabrication of devices for microfluidic bioassays and lab-on-fiber sensors. This paper describes the unique characteristics of femtosecond laser processing and the basic concepts involved in femtosecond laser direct writing. Advanced spatiotemporal beam shaping methods are also discussed. Typical examples of microfluidic sensors fabricated using femtosecond lasers are then highlighted, and their applications in chemical and biological sensing are described. Finally, a summary of the technology is given and the outlook for further developments in this field is considered.

Surface-enhanced Raman spectroscopy (SERS) has advanced over the last four decades and has become an attractive tool for highly sensitive analysis in fields such as medicine and environmental monitoring. Recently, there has been an urgent demand for reusable and long-lived SERS substrates as a means of reducing the costs associated with this technique To this end, we fabricated a SERS substrate comprising a silicon nanowire array coated with silver nanoparticles, using metal-assisted chemical etching followed by photonic reduction. The morphology and growth mechanism of the SERS substrate were carefully examined and the performance of the fabricated SERS substrate was tested using rhodamine 6G and dopamine hydrochloride. The data show that this new substrate provides an enhancement factor of nearly 1 × 108. This work demonstrates that a silicon nanowire array coated with silver nanoparticles is sensitive and sufficiently robust to allow repeated reuse. These results suggest that this newly developed technique could allow SERS to be used in many commercial applications.

Aya Kodama, Koji Sugioka, Kazuki Kuniyoshi, Sachiko Okuyama, Chota Matsumoto, Yoshikazu ShimomuraDepartment of Ophthalmology, Kinki University Faculty of Medicine, Osaka-Sayama City, Osaka, JapanAbstract: Neovascular glaucoma (NVG) secondary to internal carotid artery (ICA) occlusion is usually resistant to treatment. We report a case of NVG with ICA occlusion improved by intravitreal bevacizumab (IVB) injection and carotid artery stent replacement (CAS), even though we did not perform panretinal photocoagulation. A 67-year-old male with NVG noted visual loss in his left eye. Magnetic resonance angiography showed left ICA occlusion. He was diagnosed with NVG secondary to ICA occlusion. The next day, we carried out IVB injection in his left eye, following which the iris and angle neovascularization regressed, and the intraocular pressure decreased to normal within a day after the injection. CAS was performed on his left ICA at a month post injection. Two months later, we reinjected bevacizumab in his left eye. His condition remained stable with no recurrence over two years. This case indicates that IVB injection and CAS are useful for early-stage NVG secondary to ICA occlusion.Keywords: bevacizumab, neovascular glaucoma, internal carotid artery occlusion, carotid artery stent replacement, vascular endothelial growth factor

There are few reports on zero-field-cooled (ZFC) magnetization measurements for Fe@FeOx or FeOx particles synthesized by laser ablation in liquids (LAL) of Fe, and the minimum blocking temperature (TB) of 120 K reported so far is still much higher than those of their counterparts synthesized by chemical methods. In this work, the minimum blocking temperature was lowered to 52 K for 4–5 nm α-Fe2O3 particles synthesized by femtosecond laser ablation of Fe in acetone. The effective magnetic anisotropy energy density (Keff) is calculated to be 2.7–5.4 × 105 J/m3, further extending the Keff values for smaller hematite particles synthesized by different methods. Large amorphous-Fe@α-Fe2O3 and amorphous-Fe@C particles of 10–100 nm in diameter display a soft magnetic behavior with saturation magnetization (Ms) and coercivities (Hc) values of 72.5 emu/g and 160 Oe at 5 K and 61.9 emu/g and 70 Oe at 300 K, respectively, which mainly stem from the magnetism of amorphous Fe cores. Generally, the nanoparticles obtained by LAL are either amorphous or polycrystalline, seldom in a single-crystalline state. This work also demonstrates the possibility of synthesizing single-crystalline α-Fe2O3 hematite crystals of several nanometers with (104), (113), (116) or (214) crystallographic orientations, which were produced simultaneously with other products including carbon encapsulated amorphous Fe (a-Fe@C) and Fe@FeOx core-shell particles by LAL in one step. Finally, the formation mechanisms for these nanomaterials are proposed and the key factors in series events of LAL are discussed.

Glass is an alternative solution to polymer for the fabrication of three-dimensional (3D) microfluidic biochips. Femtosecond (fs) lasers are nowadays the most promising tools for transparent glass processing. Specifically, the multiphoton process induced by fs pulses enables fabrication of embedded 3D channels with high precision. The subtractive fabrication process creating 3D hollow structures in glass, known as fs laser-assisted etching (FLAE), is based on selective removal of the laser-modified regions by successive chemical etching in diluted hydrofluoric acid solutions. In this work we demonstrate the possibility to generate embedded hollow channels in photosensitive Foturan glass volume by high repetition rate picosecond (ps) laser-assisted etching (PLAE). In particular, the influence of the critical irradiation doses and etching rates are discussed in comparison of two different wavelengths of ultraviolet (355 nm) and visible (532 nm) ranges. Fast and controlled fabrication of a basic structure composed of an embedded micro-channel connected with two open reservoirs, commonly used in the biochip design, are achieved inside glass. Distinct advantages such as good aspect-ratio, reduced processing time for large areas, and lower fabrication cost are evidenced.

The technique of laser ablation in liquids (LAL) has already demonstrated its flexibility and capability for the synthesis of a large variety of surfactant-free nanomaterials with a high purity. However, high purity can cause trouble for nanomaterial synthesis, because active high-purity particles can spontaneously grow into different nanocrystals, which makes it difficult to accurately tailor the size and shape of the synthesized nanomaterials. Therefore, a series of questions arise with regards to whether particle growth occurs during colloid storage, how large the particle size increases to, and into which shape the particles evolve. To obtain answers to these questions, here, Ag particles that are synthesized by femtosecond (fs) laser ablation of Ag in acetone are used as precursors to witness the spontaneous growth behavior of the LAL-generated surfactant-free Ag dots (2–10 nm) into different polygonal particles (5–50 nm), and the spontaneous size separation phenomenon by the carbon-encapsulation induced precipitation of large particles, after six months of colloid storage. The colloids obtained by LAL at a higher power (600 mW) possess a greater ability and higher efficiency to yield colloids with sizes of

Koji Sugioka1, Masahiko Fukuda1, Shohei Komoto1, Motoki Itahashi1, Masakazu Yamada2, Yoshikazu Shimomura11Department of Ophthalmology, Kinki University School of Medicine, Osaka-Sayama City, Osaka, Japan; 2Division for Vision Research, National Institute of Sensory Organs, National Tokyo Medical Center, Tokyo, JapanPurpose: The objective of the study was to compare the intraocular penetration levels of the newer fluoroquinolones, moxifloxacin, gatifloxacin, and levofloxacin in the rabbit’s cornea, aqueous humor, and conjunctiva after topical instillation.Methods: 0.5% moxifloxacin, 0.3% gatifloxacin, and 0.5% levofloxacin were instilled in random sequence in both eyes of nine New Zealand White rabbits at two-minute intervals. Instillation was repeated every 15 minutes for a total of three drops of each fluoroquinolone per eye. Three additional animals had only moxifloxacin instilled bilaterally using the same schedule. Sixty minutes after the final instillation, the rabbits were sacrificed for determination of corneal, aqueous humor, and conjunctival fluoroquinolone concentrations using highperformance liquid chromatography.Results: Moxifloxacin achieved significantly higher concentrations than levofloxacin and gatifloxacin in the cornea (P = 0.0102 and P = 0.0006, respectively), aqueous humor (P = 0.0015 and P < 0.0001, respectively), and conjunctiva (P = 0.0191 and P = 0.0236, respectively). Conclusions: 0.5% moxifloxacin eyedrops provided superior intraocular penetration in rabbits’ eyes compared with the two other fluoroquinolones, 0.5% levofloxacin and 0.3% gatifloxacin.Keywords: fluoroquinolone, gatifloxacin, levofloxacin, moxifloxacin, penetration, rabbit

Microfluidic devices and biochips offer miniaturized laboratories for the separation, reaction, and analysis of biochemical materials with high sensitivity and low reagent consumption. The integration of functional or biomimetic elements further functionalizes microfluidic devices for more complex biological studies. The recently proposed ship-in-a-bottle integration based on laser direct writing allows the construction of microcomponents made of photosensitive polymer inside closed microfluidic structures. Here, we expand this technology to integrate proteinaceous two-dimensional (2D) and three-dimensional (3D) microstructures with the aid of photo-induced cross-linking into glass microchannels. The concept is demonstrated with bovine serum albumin and enhanced green fluorescent protein, each mixed with photoinitiator (Sodium 4-[2-(4-Morpholino) benzoyl-2-dimethylamino] butylbenzenesulfonate). Unlike the polymer integration, fabrication over the entire channel cross-section is challenging. Two proteins are integrated into the same channel to demonstrate multi-protein patterning. Using 50% w/w glycerol solvent instead of 100% water achieves almost the same fabrication resolution for in-channel fabrication as on-surface fabrication due to the improved refractive index matching, enabling the fabrication of 3D microstructures. A glycerol-water solvent also reduces the risk of drying samples. We believe this technology can integrate diverse proteins to contribute to the versatility of microfluidics.

Femtosecond (fs) lasers have become common tools for microfabrication and nanofabrication, and a large amount of research has been carried out in this field in 2009. This paper reviews the major areas of achievement in 2009 relating to bio-microchips such as the so-called lab-on-a-chip (LOC) and optofluidics.