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Fractures of the zygoma are rarely encountered in pediatric patients. This report presents a case of a 3-year-old child who presented with a vertically split fracture of the marginal tubercle of the zygoma. The marginal tubercle, a bony portion present on the posterior border of the frontal process, assists in attaching the temporalis fascia. This patient was treated surgically with bony fixation using tissue glue. To the best of our knowledge, no cases of fracture of the marginal tubercle of the zygoma have been reported in the literature. Fractures of the marginal tubercle of the zygoma in pediatric patients may be overlooked because of their anatomic location and the musculoskeletal characteristics of these patients. Here, we discuss the clinical features of marginal tubercle fractures of the zygoma.

Morel-Lavallee lesions (MLL) create pre-fascial space by shearing the subcutaneous tissues away from the underlying fascia, in a patient with trauma. Necrosis of the overlying skin can develop over a wide area of the lesion. The lesion might be contaminated by the surgical site due to careless intrusion when treating the combined arteriopathy. A 70-year-old woman presented with avulsion of the skin over the right foot and bilateral leg pain following a car accident. Computed tomography showed bilateral popliteal artery occlusion with large hematoma on both legs. Percutaneous angioplasty was performed with successful restoration of the flow. However, the skin color changes over time. Necrosis of the skin occurred over a wide area of the right leg. Extensive debridement was performed, and the defect was covered with a skin graft. MLLs can occur in patients with multiple traumas, multiple vascular injuries, and complex skeletal injury. Vascular surgeons treating multiple traumas should be aware of the diagnostic and management options for MLL. It should be diagnosed early because it can be difficult to manage once the overlying skin develops necrosis.

Background Because many cosmetic surgery clinics are not adequately equipped to handle emergent conditions, patients often come to a university hospital when problems occur during or after cosmetic surgery. However, few in-depth studies have been conducted of this issue. Therefore, we investigated emergency department visits due to complications associated with cosmetic surgery. Methods A retrospective chart review was conducted of 38 patients who visited the emergency department of the authors’ institution due to complications associated with cosmetic surgery from July 2014 to June 2017. Results There were more women than men (30 women vs. 8 men). Their mean age was 32.4 years (range, 19–57 years). Upon presentation to the emergency department, patients’ vital signs and mental status were usually normal (27 normal vs. 11 abnormal). The types of surgery included blepharoplasty, rhinoplasty, malar/orthognathic surgery, mammaplasty, liposuction, fat grafting, and filler and botulinum toxin injections. Most patients required hospitalization (26 admitted vs. 12 discharged). Eight of the hospitalized patients required intensive care unit care, of whom two died and three experienced brain death or had permanent neurologic sequelae. Conclusions The complications were usually minor problems, despite the need for hospitalization, but some complications were life-threatening. We recommend close monitoring and maintaining an adequate injection capacity for intravenous sedative anesthesia. When any symptom or sign of a complication occurs, it is best to transfer the patient to a university hospital as soon as possible. Taking a careful medical history is always needed, even for minor procedures.

Reactive oxygen species (ROS) contribute to pathogenesis of many inflammatory skin diseases, including psoriasis. The aim of this study is to compare antioxidant protein expression in psoriasis vulgaris (PV) skin tissues with that in normal skin tissues in vivo and to evaluate the effects of dimethyl fumarate (DMF), used for the treatment of psoriasis, on ROS generation and apoptosis in a human keratinocyte cell line HaCaT. Compared with normal skin tissues, PV skin tissues showed increased protein oxidation as well as down-regulation of Nrf2 and its regulatory proteins such as HO-1 and AKR1C3. Using HaCaT cells to model DMF-induced pro-oxidant effects in the skin cells, we found that DMF treatment induced increased ROS levels and apoptotic cell death, as signified by increased proportion of cells with Annexin V-PE(+) staining and a sub-G0/G1 peak in the cell cycle. Preceding these changes, DMF treatment resulted in up-regulation of Nrf2, HO-1, and AKR1C3 proteins in these cells. Collectively, increased oxidative stress and impaired cellular anti-oxidant enzyme systems may participate in the pathogenesis of PV. DMF may exert an additive therapeutic efficacy in PV by attenuating the redox burden and subsequent oxidative damage to normal keratinocytes through activation of Nrf2 pathway relative to PV.

Primary cutaneous mucinous carcinoma (PCMC) is a rare low-grade malignant neoplasm derived from the eccrine glands. PCMC most commonly arises in the head and neck, with the eyelid being the most common site of origin. This case report describes a 51-year-old male with a painless, pigmented superficial nodular lesion over his right lower eyelid. The lesion was considered to be benign, and the initial treatment was simple excision with a 3-mm margin. However, histologic examination revealed the diagnosis of PCMC, and the patient underwent re-excision of the tumor site with an additional 3-mm margin from the initial scar. Histologic study of this second margin was free of any malignant cells. The patient experienced no postoperative complication or recurrence after 2 years. In our case, the skin lesion had benign morphologic findings and was strongly suspected to be a benign mass. Physicians should be aware of this tumor and be able to differentiate it from benign cystic or solid eyelid lesions.

The impact of optical receiver configuration on in-band crosstalk-induced penalty has been investigated in both theoretical and experimental analyses, for differential phase-shift keying (DPSK) and differential quadrature phase-shift keying (DQPSK) signals. Previously it has been shown that DPSK signals are ~6 dB more tolerant to in-band crosstalk than on-off keying (OOK) signals. However, we find that the tolerance difference between the two signals is reduced to ~3 dB when the decision threshold of the receiver is optimized to minimize the bit-error rate for each signal. Then we derive simple equations for the in-band crosstalk-induced penalty in DPSK and DQPSK signals with two different optical receiver configurations: balanced and single-ended direct-detection receivers. We confirm that the penalties obtained from our simple equations agree well with the measured results.

A simple equation for the estimation of in-band crosstalk-induced power penalty has been derived by considering the symbol peak power as well as the impact of the average intersymbol distance in various modulation formats of optical signals. The derived equation can easily estimate the in-band crosstalk-induced penalty by considering the level of crosstalk and Q-value. Among various formats of signals, the in-band crosstalk-induced penalties in on-off keying (OOK), differential quadrature phase shift keying, and pulse amplitude modulation-4 (PAM-4) signals have been estimated for comparison. From the results, we reconfirmed that the OOK non-return-to-zero signal would be 9 dB more tolerant to in-band crosstalk than the PAM-4 signal. The estimated results agreed well with the measured results.

Background Reactive oxygen species (ROS) play an important role in the induction of apoptosis under pathological conditions. Recently, a significant increase in ROS production and disrupted apoptosis mechanisms in keloids have been reported. Nuclear factor erythroid 2-related factor 2 (Nrf2) represents one of the most important cellular defense mechanisms against oxidative stress and is implicated in the regulation of apoptosis. Recently, it has been reported that Nrf2 upregulates Bcl-2, an anti-apoptotic protein. Objective To compare Nrf2 protein expression in normal skin tissues to keloid tissues. Methods ROS generation in keloid tissues was evaluated with OxyBlot analysis. Western blotting and/or immunohistochemical staining approaches were used to study expression of Nrf2 or Bcl-2 in keloid and normal skin tissues. Cellular fractionation was performed to examine subcellular distribution of Nrf2. Transfection of fibroblasts with Nrf2-specific small interfering RNA (siRNA) was conducted to understand the relationship between Nrf2 expression and apoptosis induction. Results Protein oxidation, a marker of oxidative stress, is increased in keloid tissues. Western blot analysis clearly showed that Nrf2 and Bcl-2 are downregulated in keloid tissues. Immunohistochemical staining of Nrf2 confirmed the results of the western blot analysis. Transfection of fibroblasts with the Nrf2-specific siRNA results in increased apoptosis and decreased cell viability. Conclusion Collectively, our data indicate that Nrf2 expression is downregulated in keloid tissues, and that Nrf2 is involved in the development of apoptosis in Nrf2 siRNA-transfected fibroblasts. We propose that a defective antioxidant system and apoptotic dysregulation may participate in keloid pathogenesis.

The impact of equivalent optical bandwidth on the performance of a system using a reflective electroabsorption modulator (R-EAM) based optical source has been experimentally evaluated with signals operating at 2.5 Gb/s and beyond. The equivalent optical bandwidth of our source with a broadband seed light was simply adjusted by using a bandwidth tunable optical filter. From the measurements, we have estimated the required equivalent optical bandwidth of our source for an error-free transmission (@ bit-error-rate of $10^{-12}$ ) and a forward error correction (FEC) threshold of $2{\times}10^{-4}$ .

We demonstrate a spectrum-sliced wavelength-division-multiplexed passive optical network with the channel spacing of 25 GHz, where even and odd channels are spectrum sliced separately using a pair of 50-GHz arrayed-waveguide gratings (AWGs). The 50-GHz AWGs have an offset of 25 GHz with respect to each other. Similarly, the demultiplexing is done using a pair of 50-GHz AWGs for even and odd channels separately. Our use of 50-GHz AWGs gives better bit-error rate performances than using 25-GHz AWGs in a conventional way. With 50-GHz AWGs, the channel bandwidth is increased about two times larger than using 25-GHz AWGs. Moreover, the increased spectral overlap between adjacent channels produces relatively small crosstalk since the channels are incoherent and their intensity noise is absorbed by reflective semiconductor amplifiers. The 25-GHz spaced spectrum-sliced WDM passive optical network can be realized more easily using 50-GHz AWGs since 50-GHz AWGs are more available in the market than 25-GHz AWGs.

The validity of applying the Modified Airy Function (MAF) method to the problems of graded-index optical waveguides and graded potential barrier analysis was critically examined. In the former case, the method yielded very accurate results from the derived eigenvalue equations. In the latter case, however, the same method produced results that deviated significantly from exact numerical results for barriers with a smooth peak. The causes of the discrepancies were investigated in detail.

Background The authors retracted the infraorbital nerve (ION) using a vessel loop to explore the orbital floor fracture site and analysed when the traction of the ION was needed. Methods In ninety-one patients, the location of the fracture according to its position relative to the infraorbital groove, the location of the infraorbital groove from the midpoint of the orbital floor, and involvement of the ION in the fracture site were recorded retrospectively from computed tomography scans. An analysis of any associations between the traction of ION and the location of the fracture and ION passage was performed. Results Traction of the ION was performed in 14 cases, of which 10 cases had involvement of the ION in the fracture site and 4 cases did not. All of them were posterior fractures. In 51 cases with posterior fractures, the ION passage in patients who had ION traction was statistically located more medially (0.50 ± 1.19 mm) than in patients who had no traction (2.38 ± 1.12 mm) ( p Conclusion The ION may interfere with the exposure of the fracture site in a posterior orbital floor fracture with the involvement of the ION in the fracture site and a medially located ION passage.

Background Reactive oxygen species (ROS) damages cell molecules, and modifies cell signaling. The nuclear factor E2-related factor (Nrf2) is a critical transcription regulator, which protects cells against oxidative damage. Nrf2 expression is increased in a large number of cancers. However, little information has been reported regarding the expression of Nrf2 in skin cancers. Hence, we explored the expression of Nrf2 protein in skin cancers. Methods The Nrf2 protein expression in 24 specimens, including 6 malignant melanomas (MM), 6 squamous cell carcinomas (SCC), 6 basal cell carcinomas (BCC), and 6 normal skin tissues, was evaluated by western blotting. Immunohistochemical staining was performed. The expression of Kelch-like ECH-associated protein 1 (Keap1), the key regulator of Nrf2, was also analyzed by western blotting. Results Small interfering RNA transfection to the melanoma cell line G361 confirmed that an approximately 66 kDa band was the true Nrf2 band. The western blot revealed that the Nrf2 protein was definitely expressed in normal skin tissues, but the Nrf2 expression was decreased in MM, SCC, and BCC. Immunohistochemical examination showed that expression of Nrf2 was decreased in all skin cancer tissues compared to the normal skin tissues. Keap1 was not expressed in all malignant skin tumors and normal skin tissues by western blot. Conclusions ROS was increased in various types of cancers which proteins were highly expressed or underexpressed. This study demonstrated that the expression of Nrf2 protein was down-regulated in human malignant skin tumors. We suggest that decreased expression of Nrf2 is related to skin cancers.

Injury to the peripheral sensory branches of the trigeminal nerve can follow a wide variety of craniofacial injuries. Many patients with facial fractures complain about the symptom of numbness to the distribution of injured nerve, which is indicative of hypoesthesia. Hyperesthesia involving the infraorbital nerve is rare in comparison to hypoesthesia secondary to facial trauma. The authors report on 2 patients with infraorbital nerve hyperesthesia in surgically repaired orbital fracture patients. Surgical decompression of the infraorbital nerve led to rapid resolution of hyperesthesia. To the best of our knowledge, these were rare cases of patients who presented with persistent hyperesthesia. Clinician should perform early surgical decompression of the infraorbital nerve in patient with persistent hyperesthesia of the infraorbital nerve.

We have demonstrated an amplified wavelength-division multiplexed (WDM) passive optical network (PON) by using broadband light source (BLS) seeded optical sources and chirped fiber Bragg gratings (FBGs) based dispersion compensators. Chirped FBGs located at central office (CO) were fabricated and used as channel-by-channel dispersion compensators in order to mitigate the dispersion-induced distortion of both downstream and upstream signals. Owing to a low insertion loss of chirped FBG based dispersion compensator, the optical signal-to-noise ratio (OSNR) of the downstream signal could be improved to be ~28 dB. Thus, we re-confirmed that an error-free transmission of 1.25 Gb/s signals over a 100 km single-mode fiber (SMF) link could be achieved with a proposed amplified WDM-PON architecture. We have also evaluated the impact of various noises on the system's performance, and found that the low OSNR of the downstream signal would be a main limiting factor on the maximum reach of the proposed amplified WDM-PON architecture. From the measured ~13 dB improvement in OSNR of the downstream signal compared to our previously-proposed dispersion compensating module based scheme, we believe that the proposed architecture can accommodate a reach of longer than 100 km SMF link easily.

Type-1 neurofibromatosis, a common autosomal dominant disease, is also known as von Recklinghausen disease. Surgical procedures to treat this condition are challenging because of the brittleness of the surrounding blood vessels and soft tissues that bring the risk of causing fatal bleeding. With improvements in neurovascular embolization procedures, some literatures have been published about the application of preoperative embolization for neurofibromatosis. This case report describes a 60-year-old female with Type-1 neurofibromatosis, who presented giant facial neurofibromas with intratumoral hemorrhage on both cheeks. This patient demonstrates that these huge and challenging lesions can be successfully treated with preoperative embolization and surgical treatment. We also discuss the timing of surgical treatment with such lesions.

We propose and experimentally demonstrate a novel wavelength-division-multiplexed passive optical network (WDM-PON) scheme for providing broadcasting service by using an inverted amplified spontaneous emission (ASE) from a semiconductor optical amplifier (SOA). In this scheme, single pump signal is converted into multiple wavelengths signal by spectrum sliced wavelength conversion. We expect it could be very practical and cost-effective solution for broadcasting in WDM-PON due to its simplicity.

We demonstrated the feasibility of an amplified wavelength-division multiplexed passive optical network (WDM-PON) architecture based on broadband light source (BLS) seeded optical sources and a novel bidirectional reach extender. Our bidirectional reach extender could provide an amplification of both downstream and upstream signals as well as a BLS output for the upstream WDM signal generation. An error-free 1.25 Gb/s signal transmission over a 100-km long single-mode fiber was achieved in a bidirectional WDM-PON using BLS seeded reflective semiconductor optical amplifier (RSOA) sources.

Background TC21 plays an important role in highly aggressive tumor formation, and it was overexpressed in several human cancers, including breast cancer, oral squamous cell carcinoma (SCC), and esophageal SCC. In light of this, we explored the expression of TC21 in overall skin cancers in order to evaluate the relationship between TC21 and malignant skin tumors. Methods We examined six normal skin tissues and 18 malignant skin tumor tissues, including six malignant melanomas (MM), six SCCs, and six basal cell carcinomas (BCCs) using western blotting for the expression of TC21. In another set, 16 specimens of MM, 16 SCC, and 16 BCC were analyzed for the expression of TC21 using immunohistochemical staining. To evaluate the amount of expression of TC21, the Raytest TINA software was used for western blotting and a histochemical score (HSCORE) was used for immunohistochemical evaluation. Results The western blotting and immunohistochemistry showed that TC21 was expressed in all malignant skin tumors and not in normal skin tissues. The relative protein expression was an average of 0.004 in normal skin, 1.042 in MM, 0.621 in SCC, and 0.485 in BCC. In immunohistochemistry, HSCORE for normal skin was an average of 0.05, MM was 2.42, SCC was 2.11, and BCC was 1.22. Conclusions This article is the first study demonstrating expression of TC21 in human skin malignant tumors and suggests that TC21 is more expressed in highly aggressive skin tumors.

We have evaluated the performances of bidirectional optical amplifiers which were suited for the cost-effective implementation of amplified bidirectional passive optical networks (PONs). First, we measured the maximum gains of two simple bidirectional optical amplifiers implemented without using any optical components for the suppression of reflected signals. From the results, the maximum gains of two simple bidirectional amplifiers with a broadband light source (BLS) seeded optical source were limited to be 27 dB due to the reflection-induced in-band crosstalk, when the reflectance coefficients were measured to be -33 dB in both directions. Then, we have also implemented a bidirectional optical amplifier with two band splitters for the amplified bidirectional PON where the two different wavelength bands were allocated to the downstream and upstream signals transmission. In our measurement, we confirmed that the maximum gain of bidirectional optical amplifier with two band splitters could be increased to more than 30 dB owing to the efficient suppression of in-band crosstalk.

Primary mucosal melanomas of the head and neck are rare. In addition, second primary mucosal melanoma following primary cutaneous malignant melanomas is very rare. We report a second primary mucosal melanoma. A 76-year-old woman, who had a previously cutaneous malignant melanoma of the left foot, visited with a complaint of a foreign body sensation of the throat. Endoscopy revealed a black mass at the left piriform sinus of the hypopharynx. After wide surgical excision of the lesion and reconstruction with a radial forearm free flap, the histopathology was confirmed to be a second primary mucosal malignant melanoma of the hypopharynx. Five months postoperatively, masses were palpated in the neck, and metastasis was diagnosed. The patient was treated with adjuvant chemotherapy and radiotherapy. Eight months postoperatively, computed tomography scans showed other metastatic masses in the liver, spleen, both adrenal glands, soft tissues of the abdominal wall, and both lungs. After that, the patient died 9 months postoperatively. We report a rare case of second primary mucosal malignant melanoma of the hypopharynx. Although rare, this case shows that a detailed examination of the hypopharynx and the head and neck should be a part of the follow-up examination in all cutaneous malignant melanoma patients.

Fractures of the hyoid bone are commonly caused by strangulation or hanging [1]. However, fractures of the hyoid bone resulting from trauma other than strangulation or hanging are rare [1]. A hyoid bone fracture is occasionally associated with clinically significant complications including airway obstruction [2,3]. Although many facial injuries are caused by trauma, a fracture of the hyoid bone complicating a facial fracture is rare [4]. Herein, we report a hyoid bone fracture. A 32-year-old man presented to our emergency room complaining of painful swelling in the left mandible area aftera a car accident. He was in an alert mental state. Physical examination revealed severe tenderness over the left mandible angle region. Occlusal disturbance was noted. Plain radiography demonstrated a left angle fracture of the mandible (Fig. 1). An X-ray of the neck did not show a definite fracture (Fig. 2). The mandibular fracture was treated by open reduction and internal fixation with a plate (Fig. 3). Two days after the operation for the mandibular fracture, he complained of dyspnea that suddenly develpoed. Physical examination revealed crepitus and pain in the anterior neck upon turning the face. Pharyngolaryneal edema was identified. The patient was transferred to the intensive care unit. After 5 days of close observation, his symptoms subsided. He underwent a computed tomography (CT) scan of the neck to rule out the presence of damage to airway structures. CT demonstrated a slightly displaced fracture of the hyoid bone between the left greater horn and the body (Fig. 4). There was no perforation in the larynx or pharynx, and the cervical spines and other airway structures were normal. Direct laryngoscopy was normal. He was diagnosed with a fracture of the hyoid bone. Management was conservatively. Fortunately, his symptoms disappeared after 2 weeks. Fig. 1 A postero-anterior view of mandible revealed a left angle fracture. Fig. 2 Routine lateral radiography showed no definite fracture line. Fig. 3 A postoperative view of a mandibular fracture. Fig. 4 (A) A cervical computed tomography (CT) scan showed a slightly displaced fracture of the hyoid bone between the left greater horn and the body. (B) A three dimensional CT scan of the hyoid bone. Facial trauma is commonly encountered in the department of plastic surgery. However, hyoid bone fractures secondary to trauma other than strangulation or hanging are rare, because the hyoid bone is well protected by the mandible and the cervical spine [1]. The hyoid bone is not directly articulated to other bones, and the stylohyoid ligament suspends the hyoid bone to the tips of the styloid process [1]. The hyoid bone also provides the attachment site of the pharynx to maintain the patency of the pharynx during swallowing and respiration. Therefore, a fracture of the hyoid bone can result in a compromised airway [3]. Papavasiliou and Speas [2] reported that upper airway obstruction was associated with a hyoid bone fracture. Krekorian [3] reported that fragments of a fractured hyoid bone resulted in the perforation of the pharynx. As the hyoid bone was related to the surrounding structures, hyoid bone fractures have been reported with associated injuries including cervical spine injuries, damage to the larynx or pharynx, and facial fractures [2-4]. These associated injuries tend to need more urgent management and, as a result, a fracture of the hyoid bone may not be recognized immediately. In our patient, the hyoid bone fracture was masked by the mandibular fracture. The symptoms of a hyoid bone fracture can clinically vary, including worsening of neck pain by coughing or swallowing, crepitus, dyspnea, and hemoptysis [1]. Diagnosis of a hyoid bone fracture is difficult and is usually performed upon a clinically strong suspicion of a surgeon [5]. In general, a hyoid bone fracture is clearly visible in plain radiographs of the cervical spine [5]. However, in our case, an X-ray did not reveal a definite fracture line. Later, a CT scan showed an interruption of the cortex in the diagnosis of hyoid bone fracture. Similarly, the diagnosis of a hyoid bone fracture may be overlooked, particularly in the presence of a more striking and serious injury such as the mandibular fracture seen in our case. Although the dyspnea symptom of our patient was fortunately resolved, a hyoid bone fracture should be observed for 48 to 72 hour because hyoid bone fractures may lead to the development of significant problems including respiratory distress [1-5]. In the case of airway obstruction, tracheostomy or endotracheal intubation must be performed [4]. A mandibular fracture produces swelling on the soft tissue of the neck, which may mask an associated hyoid fracture. Although a traumatic fracture of the hyoid bone is rare, considerably more attention should be paid to a patient with facial trauma and a close follow-up is necessary because a hyoid bone fracture is difficult to diagnose and can be easily overlooked in the initial evaluation of trauma, leading to potentially life-threatening circumstances. Therefore, the surgeon must be aware of the possibility of an underlying hyoid bone fracture in patients of facial trauma.

A novel scheme for the suppression of intra- wavelength-channel mode competition in a multiwavelength SOA-based ring laser is proposed and experimentally demonstrated. The scheme is based on coupled ring cavities, which act as mode filters to suppress the side mode frequencies. The proposed scheme performance is evaluated in terms the output power, long term stability, and side-mode suppression ratio of the proposed SOA-based ring laser. A side mode suppression ratio lager than 10 dB is readily achieved by incorporating a subcavity inside a main ring cavity, due to Vernier effect induced by the coupled dual cavities. Also is investigated the possibility of the use of the noise-reduced multiwavelength laser as a transmitter light source within wavelength division-multiplexed passive optical network.

The author reports a rare case of Horner syndrome in a patient who resulted from stenosis of the vertebral artery after blunt trauma. A 31-year-old man was transferred to our department for evaluation of left medial orbital wall and nasal bone fractures. Five days ago, he was hospitalized due to multiple second to fourth rib fractures of the right chest following blunt trauma of the face, neck, and chest. Surgery was performed. Ten days later, he complained of drooping of the right eyelid. Physical examination revealed a discrete miosis and ptosis with normal levator function in the right eye. A workup for Horner syndrome was performed. Magnetic resonance angiography of the head and neck revealed a stenosis of the distal part of the right vertebral artery without the abnormality of carotid artery. He wore a cervical collar and underwent anticoagulation. However, Horner syndrome was not resolved over the next 12 months. Acute traumatic Horner syndrome may be associated with vertebral artery dissection in which the possibility of life-threatening injury can be masked.

We investigate the benefits of using our proposed continuous-wave supercontinuum (CW SC) as a broadband wavelength-locking source for the implementation of extended-reach, colorless, wavelength division-multiplexed passive optical networks (WDM-PONs). More specifically, first, an extended reach WDM-PON architecture based on both the CW SC and our devised C-/L-band beam combiner is proposed, in which the optical line terminal (OLT) is based on Fabry–Perot laser diodes (FP-LDs), whereas the optical network units (ONUs) are reflective semiconductor optical amplifiers (RSOAs). Second, a theoretical investigation on the maximum reach achievable with the proposed architecture is carried out considering Rayleigh backscattering noise and injection power limits. Only upstream signal performance is compared for the following four cases: (1) superluminescent diode (SLD) broadband source and FP-LD ONU, (2) SLD and RSOA, (3) CW SC and FP-LD, and (4) CW SC and RSOA. The combination of a CW SC injection source and RSOA-based ONUs is found to allow for the longest distance coverage. Finally, the feasibility of the proposed architecture is experimentally analyzed over a 60-km transmission fiber at 622 Mbit/s.

We have evaluated the performance of strain-chirped fiber Bragg grating (FBG) based tunable dispersion compensator in a 40 Gb/s transmission link. In our proposed compensator, the value of dispersion could be changed from -353 ps/nm to -962 ps/nm by adjusting the rotation angle of the metal beam on which the FBG was mounted. In order to evaluate the effect of ripples in reflectivity and variations in passband of the FBG based dispersion compensator, transmission performance has been measured with our tunable dispersion compensator. Error-free transmission of a 40 Gb/s non-return-to-zero (NRZ) signal over conventional single-mode fiber (SMF) was achieved.

We propose and experimentally demonstrate a novel bidirectional wavelength-division-multiplexed passive optical network architecture that fully utilizes the superior optical properties of an incoherent continuous-wave (CW) supercontinuum (SC) source. The proposed architecture, which incorporates low-cost Fabry-Perot laser diodes that have been wavelength locked by spectrum-sliced beams from a depolarized 130-nm-bandwidth CW SC source, is based on a unique wavelength band allocation scheme of the C-band for an optical line terminal (OLT), the L-band for optical network units (ONUs), and the U-band for channel monitoring. A cost-effective network that features a single broadband source at the OLT, and no additional wavelength- band-selective monitoring beam reflector at each ONU can be readily achieved. The experimental demonstration presented in this paper is carried out at a data rate of 622 Mb/s over a 25-km standard single-mode fiber.

In response to persistent mycobacteria infection, the host induces a granuloma, which often fails to eradicate bacteria and results in tissue damage. Diverse host receptors are required to control the formation and resolution of granuloma, but little is known concerning their regulatory interactions. Here we show that Mincle, the inducible receptor for mycobacterial cord factor, is the key switch for the transition of macrophages from cytokine expression to high nitric oxide production. In addition to its stimulatory role on TLR-mediated transcription, Mincle enhanced the translation of key genes required for nitric oxide synthesis through p38 and eIF5A hypusination, leading to granuloma resolution. Thus, Mincle has dual functions in the promotion and subsequent resolution of inflammation during anti-mycobacterial defence using both transcriptional and translational controls., Resolution of granulomas in mycobacterial infection requires macrophages to switch from cytokine to nitric oxide (NO) production. Here the authors show that Mincle stimulates translation of the key NO synthesis genes by a mechanism dependent on p38-mediated hypusination of eiF5A.

The authors report a rare case of Horner syndrome in a patient with neurofibromatosis type 1 (NF-1). A 31-year-old man visited the clinic with drooping left eyelid. The physical examination revealed ptosis of the left eyelid, miotic pupil, facial anhidrosis, and several skin masses on the chest. The radiological examination of the chest demonstrated a well-defined left posterior mediastinal mass close to the vertebral bodies of the upper thoracic spine at the level of T1-T5. The masses of mediastinum and skin were totally removed. They were diagnosed as neurofibromas. Neurofibromatosis type 1 was diagnosed. To the best of my knowledge, this is a rare case of a patient with NF-1 who presented with Horner syndrome. Clinicians should be vigilant on the possibility of Horner syndrome in patients with NF-1.