Ileocecal junction perforation by colonic T-cell lymphoma in a patient with primary Sjögren's syndrome.

Primary Sjögren's syndrome (pSS) is associated with an increased risk of lymphoma, especially non-Hodgkin's lymphoma. The rarest pathological subtype is T-cell lymphoma. We herein report a case of a 52-year-old man with a 17-year history of pSS who was admitted to our hospital with chronic epigastric pain and a positive fecal occult blood test. Colonoscopy revealed multiple colonic ulcers, and histological and immunological studies demonstrated the T-cell origin of this lymphoma. However, the patient rejected all treatments. He developed recurrent intestinal obstruction and infection for 3 years until an intestinal perforation occurred. The right half of the colon was resected and colostomy was performed. However, the patient died of an intestinal fistula and intraperitoneal infection 40 days postoperatively. This case highlights the rarity of the correlation between T-cell lymphoma and pSS.

Low Power Consumption Substrate-Emitting DFB Quantum Cascade Lasers.

In the present work, an ultra-low power consumption substrate-emitting distributed feedback (DFB) quantum cascade laser (QCL) was developed. The continuous-wave (CW) threshold power dissipation is reduced to 0.43 W at 25 °C by shortening the cavity length to 0.5 mm and depositing high-reflectivity (HR) coating on both facets. As far as we know, this is the recorded threshold power dissipation of QCLs in the same conditions. Single-mode emission was achieved by employing a buried second-order grating. Mode-hop free emission can be observed within a wide temperature range from 15 to 105 °C in CW mode. The divergence angles are 22.5o and 1.94o in the ridge-width direction and cavity-length direction, respectively. The maximum optical power in CW operation was 2.4 mW at 25 °C, which is sufficient to spectroscopy applications.

Room temperature continuous wave quantum dot cascade laser emitting at 7.2 µm.

We demonstrate a quantum cascade laser with active regions consisting of InAs quantum dots deposited on GaAs buffer layers that are embedded in InGaAs wells confined by InAlAs barriers. Continuous wave room temperature lasing at the wavelength of 7.2 µm has been demonstrated with the threshold current density as low as 1.89 kA/cm2, while in pulsed operational mode lasing at temperatures as high as 110 °C had been observed. A phenomenological theory explaining the improved performance due to weak localization of states had been formulated.

High Efficiency, Low Power-Consumption DFB Quantum Cascade Lasers Without Lateral Regrowth.

Very low power-consumption distributed feedback (DFB) quantum cascade lasers (QCLs) at the wavelength around 4.9 µm were fabricated by conventional process without lateral regrowth of InP:Fe or using sidewall grating. Benefitted from the optimized materials and low waveguide loss, very low threshold current density of 0.5 kA/cm2 was obtained for a device with cavity length of 2 mm. Combined with the partial-high-reflection coating, the 1-mm-long DFB QCL achieved low power-consumption continuous wave (CW) operation up to 105 °C. The CW threshold power-consumptions were 0.72 and 0.78 W at 15 and 25 °C, respectively. The maximum CW output power was over 110 mW at 15 °C and still more than 35 mW at 105 °C. At 15 °C, wall-plug efficiency of 5.5% and slope efficiency of 1.8 W/A were deduced, which were very high for low power-consumption DFB QCLs.

High efficiency, single-lobe surface-emitting DFB/DBR quantum cascade lasers.

We demonstrate a surface-emitting quantum cascade laser (QCL) based on second-order buried distributed feedback/distributed Bragg reflector (DFB/DBR) gratings for feedback and outcoupling. The grating fabricated beneath the waveguide was found to fundamentally favor lasing in symmetric mode either through analysis or experiment. Single-lobe far-field radiation pattern with full width at half maximum (FWHM) of 0.18° was obtained along the cavity-length direction. Besides, the buried DFB/DBR grating structure successfully provided an efficient vertical outcoupling mechanism with low optical losses, which manages to achieve a high surface outcouping efficiency of 46% in continuous-wave (CW) operation and 60% in pulsed operation at room temperature. Single-mode emission with a side-mode suppression ratio (SMSR) about 25 dB was continuously tunable by heat sink temperature or injection current. Our work contributes to the realization of high efficiency surface-emitting devices with high far-field beam quality that are significantly needed in many application fields.

[Factors of prognosis in cervical spondylotic myelopathy: a review].

Cervical spondylotic myelopathy (CSM) is a common cause of spinal cord dysfunction clinical disease. Surgery is the main therapeutic tool for CSM. However, there are obvious differences in clinical functional recovery after operation. For the past few years, the influence factors of prognosis in cervical spondylosis myelopathic has been widely concerned. Age, nerve function, course of desease, imaging findings,surgical method and related factors became the investigative point for prognosis of cervical spondylotic myelopathy. Present viewpoint showed that the older patient, preoperative worse nerve function, longer the course of disease would result in worse outcomes. Imaging examination maybe can indicate the prognosis, but the correlation is unclear. Selection of surgical method and approach should be based on the principles of sufficient decompression, stabilize the alignment of the cervical spine, keeping backward extension of cervical spine, maintain effective decompression, preventing complications. Therefore, the treatment of cervical spondylotic myelopathy should be on the basis of pathogenic condition and imaging examination at early stage and a suitable usrgical procedure should be performed to obtain a better prognosis.

10-W pulsed operation of substrate emitting photonic-crystal quantum cascade laser with very small divergence.

High-power broad area substrate emitting photonic-crystal distributed feedback (DFB) quantum cascade lasers (QCLs) emitting around 4.73 µm is reported. Two-dimensional centered rectangular photonic-crystal (CRPC) grating is introduced to enhance optical coherence in large area device. Main lobe far-field radiation pattern with a very small divergence angle of about 0.65° × 0.31° is obtained. A record peak output power for vertical emitting QCLs exceeding 10 W is obtained with high reflectivity (HR) coating. Robust single longitudinal mode emission with a side mode suppression ratio (SMSR) of 30 dB is continuously tunable by the heat sink temperature up to 65°C.

Growing trend of China's contribution to the field of spine: a 10-year survey of the literature.

PURPOSE: China, as a rapidly developing country with the largest population including over 50,000 orthopaedic surgeons, has an increasing importance in the field of spine. However, the quantity and quality of research production in the field of spine in the major regions of China-Mainland China, Taiwan, and Hong Kong is unclear. This study aimed to investigate the contribution of China to the field of spine. METHODS: Articles published in the 5 major spine journals originating from Mainland China, Taiwan and Hong Kong in 2004-2013 were retrieved from the database of Web of Science. The number of articles, impact factors, citations, article type, city, institution, funding source and conflict of interest were analyzed. RESULTS: There were 1006 publications in the 5 spine journals between 2004 and 2013 from China, including 706 from Mainland China, 210 from Taiwan, and 90 from Hong Kong. The time trend of the number of articles from these three regions showed a significant increase of 8.74-fold (from 23 to 201) between 2004 and 2013 (p = 0.000). From 2006, the number of publications from Mainland China exceeded Taiwan and Hong Kong. Mainland China had the highest total impact factors (1686.54) and total citations (4214), followed by Taiwan (498.93; 2009) and Hong Kong (222.89; 1311). Hong Kong had the highest mean impact factor (2.48) and mean citations (14.46), followed by Mainland China (2.40; 10.26) and Taiwan (2.38; 10.14). The journal Spine published the largest number of articles (470), followed by European Spine Journal (268). CONCLUSIONS: Chinese contributions to the field of spine have a significant increase during the past 10 years, particularly from Mainland China. Hong Kong had the highest quality research output in terms of mean impact factor and mean citation per article.

Small divergence substrate emitting quantum cascade laser by subwavelength metallic grating.

Metallic periodic structure in subwavelength scale offers an exciting way to couple light into surface plasmons (SPs), thus manipulating the properties of near-field optics. We show that subwavelength metallic grating (SMG) defined on the substrate side of substrate emitting quantum cascade lasers enables far-field improvement in mid-infrared spectrum. The SMG is designed to tailor the interaction of SPs with single mode transverse magnetic light. The experiment results are in good agreement with the simulated model. A far-field full width at half maximum (FWHM) divergence angle of 3.9 ° in the direction perpendicular to the laser waveguide layers is obtained, improved by a factor of 8.5 compared with traditional surface emitting device.

Fifty top-cited classic papers in orthopedic elbow surgery: A bibliometric analysis.

OBJECTIVE: The number of citations that a paper has received reflects the impact of the article within a particular medical area. Citation analysis concerning the most cited articles have been widely reported in orthopedic surgery and its subspecialties. However, which articles are cited most frequently in orthopedic elbow surgery is unknown. This study aimed to identify and analyze the characteristics of the 50 most cited articles in elbow surgery. METHODS: Science Citation Index Expanded was used to search for citations in 181 journals chosen according to the relevance for elbow publications. The 50 most cited articles in elbow surgery were identified. The title, authors, year of publications, article type, journal source, country, institution, number of citations, decade published, citation density and level of evidence were recorded and analyzed. RESULTS: The 50 most cited articles were published between 1950 and 2010. The 1980s was the most productive decade. The number of citations ranged from 388 to 124. All the articles were written in English and published in nine journals. The majority of articles originated from United States, followed by Canada and United Kingdom. Fracture was the most discussed topic. The majority of the top cited articles were clinical studies, with the remaining basic research. The most common level of evidence was level IV. CONCLUSIONS: Identification of the most cited papers in elbow surgery shows an insight into the historical development of elbow surgery and provides the foundation for further investigations.

[Reasearch on mechanism of neurotrophins in discogenic low back pain].

Discogenic low back pain is the common type of chronic low back pain. However,its mechanism has not been completely clarified. Considerable evidence shows that neurotrophins play an important role in discogenic low back pain. The paper summarizes the mechanism of neurotrophins on discogenic low back pain according to the pain transfer pathway of neurotrophins in intervertebral disc, dorsal horn ganglia and spinal trigeminal nucleus. Changing the pain transmission by regulating neurotrophins and its receptor will provide a new way for the treatment of discogenic low back pain.

[Comparative studies on the characteristics for Cu2+ or Zn2+ adsorption onto different landfilled sludge].

In this paper, it was comparatively studied about the adsorption or desorption behaviour for Cu2+ or Zn2+ ion onto different landfilled sludge. The results showed that Cu2+ or Zn2+ adsorption isotherm could significantly conform to Freundlich and Henry equations both for the directly landfilled sludge (SSA) and the solidifying landfilled sludge (SSB). Moreover, much higher adsorption capacities were found for Cu2+ on SSA but for Zn2+ on SSB, and the removal efficiency could reach 95% for Cu2+ by SSA with dosage being 10-20 g/L or Zn2+ by SSB with dosage being 5 g/L when the initial CU2+ or Zn2+ concentration was 128 mg/L. However, the desorption ratio of Cu2+, Zn2+ decreased with their increasing adsorption amount, with the same initial concentration, it was much more difficult for Cu2+ to release from SSA while for Zn2+ to release from SSB. Relatively, first-order dynamic equation was the optimal model to describe the kinetics of Cu2+, Zn2+ adsorption by the two sludges, the rates for Cu2+ adsorbed onto SSA and for Zn2+ adsorbed onto SSB were much higher at the same adsorption time. FTIR analysis showed that, the site for Cu2+ adsorption onto SSA is the Si-O group from silicate and carboxy groups from aromatic acids or fatty acids which making stable complex compound with CU2+, while it was specific adsorption by Me--O group from metal oxide and hydroxyl group or carboxy groups from fatty acids for Zn2+ adsorption onto SSB.