Solar background noise mitigation using the orbital angular momentum mode in vertical FSO downlink transmissions.

Free-space optical communication (FSO) is used to provide network configuration flexibility. A network-flying platform-based vertical FSO connection can be employed to enhance mobile network coverage and capacity. Solar background noise can be a potential risk that disrupts the seamless connection in the vertical FSO downlink channel. In this paper, we propose signal transmission using an orbital angular momentum (OAM) beam. The OAM demodulation process can filter sunlight out of the optical receiver except for the signal corresponding to the azimuthal state. We experimentally verified that most of the solar background noise could be reduced. To verify the feasibility of the proposed scheme in a vertical FSO channel, we modeled a FSO vertical downlink with an OAM modulation/demodulation process.

Site-dependent changes in structure and function of lapine articular cartilage 4 weeks after anterior cruciate ligament transection.

OBJECTIVE: The aim of this study was to investigate the site-dependent changes in the structure and function of articular cartilage in the lapine knee joint at a very early stage of osteoarthritis (OA), created experimentally by anterior cruciate ligament transection (ACLT). METHODS: Unilateral ACLT was performed in eight mature New Zealand white rabbits. ACL transected and contralateral (C-L) joints were prepared for analysis at 4 weeks after ACLT. Three rabbits with intact joints were used as a control group (CNTRL). Femoral groove, medial and lateral femoral condyles, and tibial plateaus were harvested and used in the analysis. Biomechanical tests, microscopy and spectroscopy were used to determine the biomechanical properties, composition and structure of the samples. A linear mixed model was chosen for statistical comparisons between the groups. RESULTS: As a result of ACLT, the equilibrium and dynamic moduli were decreased primarily in the femoral condyle cartilage. Up to three times lower moduli (P < 0.05) were observed in the ACLT group compared to the control group. Significant (P < 0.05) proteoglycan (PG) loss in the ACLT joint cartilage was observed up to a depth of 20-30% from the cartilage surface in femoral condyles, while significant PG loss was confined to more superficial regions in tibial plateaus and femoral groove. The collagen orientation angle was increased (P < 0.05) up to a cartilage depth of 60% by ACLT in the lateral femoral condyle, while smaller effects, but still significant, were observed at other locations. The collagen content was increased (P < 0.05) in the middle and deep zones of the ACLT group compared to the control group samples, especially in the lateral femoral condyle. CONCLUSION: Femoral condyle cartilage experienced the greatest structural and mechanical alterations in very early OA, as produced by ACLT. Degenerative alterations were observed especially in the superficial collagen fiber organization and PG content, while the collagen content was increased in the deep tissue of femoral condyle cartilage. The current findings provide novel information of the early stages of OA in different locations of the knee joint.

Randomised controlled clinical trial for autologous fibroblast-hyaluronic acid complex in treating diabetic foot ulcers.

OBJECTIVE: Diabetic foot ulcers (DFUs) often pose a treatment problem. Bioengineered skin substitutes have been reported to result in accelerated diabetic wound healing. The purpose of this clinical trial was to evaluate the efficacy and safety of the autologous fibroblast-hyaluronic acid complex for treating DFUs. METHOD: A stratified, randomised, controlled, multicentre study was carried out. Patients with DFUs were allocated to either a treatment group with grafting of an autologous fibroblast-hyaluronic acid complex or a control group with non-adherent foam dressing. Except for application of the fibroblast complex, treatment of the study ulcers was identical for patients in both groups. The maximum follow-up period for each patient was 12 weeks. RESULTS: Complete ulcer healing was achieved in 84% (26/31 patients) of the treatment group and 34% (11/32 patients) of the control group (p<0.05). The times required for complete healing were 36.4 ± 17.6 and 48.4 ± 13.1 days in the treatment and control groups, respectively (p<0.05). No adverse events related to treatment occurred. CONCLUSION: These results indicate that autologous fibroblast-hyaluronic acid complex may offer a safe and effective treatment for DFUs.

Cell deformation behavior in mechanically loaded rabbit articular cartilage 4 weeks after anterior cruciate ligament transection.

OBJECTIVE: Chondrocyte stresses and strains in articular cartilage are known to modulate tissue mechanobiology. Cell deformation behavior in cartilage under mechanical loading is not known at the earliest stages of osteoarthritis. Thus, the aim of this study was to investigate the effect of mechanical loading on volume and morphology of chondrocytes in the superficial tissue of osteoarthritic cartilage obtained from anterior cruciate ligament transected (ACLT) rabbit knee joints, 4 weeks after intervention. METHODS: A unique custom-made microscopy indentation system with dual-photon microscope was used to apply controlled 2 MPa force-relaxation loading on patellar cartilage surfaces. Volume and morphology of chondrocytes were analyzed before and after loading. Also global and local tissue strains were calculated. Collagen content, collagen orientation and proteoglycan content were quantified with Fourier transform infrared microspectroscopy, polarized light microscopy and digital densitometry, respectively. RESULTS: Following the mechanical loading, the volume of chondrocytes in the superficial tissue increased significantly in ACLT cartilage by 24% (95% confidence interval (CI) 17.2-31.5, P < 0.001), while it reduced significantly in contralateral group tissue by -5.3% (95% CI -8.1 to -2.5, P = 0.003). Collagen content in ACLT and contralateral cartilage were similar. PG content was reduced and collagen orientation angle was increased in the superficial tissue of ACLT cartilage compared to the contralateral cartilage. CONCLUSIONS: We found the novel result that chondrocyte deformation behavior in the superficial tissue of rabbit articular cartilage is altered already at 4 weeks after ACLT, likely because of changes in collagen fibril orientation and a reduction in PG content.

Association between urine cotinine levels, continuous performance test variables, and attention deficit hyperactivity disorder and learning disability symptoms in school-aged children.

BACKGROUND: We examined the cross-sectional relationship between environmental tobacco smoke exposure, continuous performance test (CPT) measures, and attention deficit hyperactivity disorder (ADHD) or learning disability symptoms in school-aged children. METHOD: In total, 989 children (526 boys, mean age 9.1 ± 0.7 years), recruited from five South Korean cities participated in this study. We used urine cotinine as a biomarker for environmental tobacco smoke exposure, and obtained the children's scores on a CPT. Parents completed the Korean versions of the ADHD rating scale-IV (ADHD-RS) and learning disability evaluation scale (LDES). Using generalized linear mixed model (GLMM), we assessed the associations between urine cotinine concentrations, neuropsychological variables, and symptoms of ADHD and learning disabilities. Additionally, we conducted structural equation models to explore the effects' pathways. RESULTS: After adjusting for a range of relevant covariates, GLMM showed urinary cotinine levels were significantly and positively associated with CPT scores on omission errors, commission errors, response time, and response time variability, and with parent- and teacher-rated ADHD-RS scores. In addition, urine cotinine levels were negatively associated with LDES scores on spelling and mathematical calculations. The structural equation model revealed that CPT variables mediated the association between urine cotinine levels and parental reports of symptoms of ADHD and learning disabilities. CONCLUSIONS: Our data indicate that environmental exposure to tobacco smoke is associated with ADHD and learning disabilities in children, and that impairments in attention and inhibitory control probably mediate the effect.

Influence of face mask design on bag-valve-mask ventilation performance: a randomized simulation study.

BACKGROUND: Different face mask designs can influence bag-valve-mask (BVM) ventilation performance during resuscitation. We compared a single-use, air-cushioned face mask (AM) with a reusable silicone face mask (SM) for quality of BVM ventilation on a manikin simulating cardiac arrest. METHODS: Thirty-two physicians were recruited, and a prospective, randomized, crossover observational study was conducted after an American Heart Association-accredited basic life support provider course and standardized practice time were completed. Participants performed 12 cycles of BVM ventilation with both the AM and SM on a SmartMan lung simulator. RESULTS: Mean tidal volume was significantly higher in ventilations performed using the AM vs. the SM (548 ± 159 ml vs. 439 ± 163 ml, P < 0.01). In addition, the proportion of low-volume ventilation was significantly lower with the AM than the SM [6/12 (2-11) vs. 9/12 (5-12), P = 0.03]. Bag-valve-AM ventilation volume was not affected by the physical characteristics of the rescuers, except for sex. In contrast, bag-valve-SM ventilation volume was affected by most of the characteristics tested, including sex, height, weight, hand width, hand length, and grip power. CONCLUSION: The AM seems to be a more efficient face mask than the SM at delivering sufficient ventilation volumes. The performance of the AM did not seem to be associated with the physical characteristics of the rescuers, whereas that of the SM was affected by these factors. The SM may not be an appropriate face mask for performing one-person BVM ventilation during resuscitation for rescuers who are smaller in stature, have a smaller hand size, or have weaker grip power.

10-Gb/s transmission over 20-km single fiber link using 1-GHz RSOA by discrete multitone with multiple access.

We demonstrate a novel 10.5-Gbit/s transmission scheme over 20-km single fiber link by using a remotely fed 1-GHz reflective semiconductor optical amplifier (RSOA). Discrete multitone (DMT) modulation with adaptive bit-/power-loading is applied to overcome the bandwidth limitation of the RSOA. Transmission performance of the proposed scheme is analyzed in terms of various system parameters, such as the nonlinearity of the RSOA, optical signal-to-noise ratio of the optical seed carrier, the overhead size impact on dispersion, the number of DMT subcarriers, and the reflection noise from the single fiber link. We also report flexible-bandwidth-allocated multiple access operation based on the proposed scheme. The throughput for all cases is approximately 10 Gbit/s with BER < 10(-3).

Optimization of selective emitter fabrication method for solar cells using a laser grooving.

In this paper, screen-printing laser grooved buried contact (LGBC) method was applied, which is compatible with the existing screen-printed solar cell equipment and facilities. Experiments were performed in order to optimize short circuit current (I(sc)), open circuit voltage (V(oc)) and fill factor of high efficiency solar cells. To enhance I(sc), V(oc) and efficiency, heavy doping was performed at low sheet resistance in the laser grooved region of the cell. In contrast, light doping was carried out at a high sheet resistance in the non-laser grooved region. To increase fill factor, porous silicon found on the wafer after dipping in an HF solution to remove SiN(x), was cleared. The fabricated screen-printing LGBC solar cell using a 125 mm x 125 mm single crystalline silicon wafer exhibited an efficiency of 17.2%. The results show that screen-printing LGBC method can be applied for high efficiency solar cells.

Impact of resistance to first-line and injectable drugs on treatment outcomes in MDR-TB.

Recently, resistance to additional first-line and injectable drugs was reported to be an independent risk factor for adverse outcomes in multidrug-resistant (MDR) tuberculosis (TB) patients. The aim of the present study was to confirm these observations in MDR-TB patients without HIV infection. MDR-TB patients treated at a tertiary referral hospital in South Korea between January 1996 and December 2005 were included. The unadjusted and adjusted odds ratios of adverse treatment outcome were calculated for resistance to each drug and combination of drugs using simple or multiple logistic regressions. None of the resistance to additional first-line or injectable drugs was associated with higher odds for adverse treatment outcome in 155 MDR but nonextensively drug-resistant (non-XDR) TB patients. However, streptomycin resistance was associated with 12 times the odds for adverse treatment outcome in 42 extensively drug-resistant (XDR) TB patients. Neither combinations of first-line drugs nor those of injectable drugs were associated with increased odds for adverse treatment outcomes in non-XDR MDR-TB patients or XDR-TB patients. Only streptomycin resistance among the first-line or injectable drugs was associated with adverse treatment outcomes in extensively drug-resistant tuberculosis patients without HIV infection.

Multidrug-resistant tuberculosis over 20 years at a referral hospital in South Korea: trends and outcomes.

SETTING: A referral centre in South Korea. OBJECTIVE: To investigate trends in drug resistance, treatment modalities and outcomes, and adverse events of multidrug-resistant tuberculosis (MDR-TB) over two decades. DESIGN: MDR-TB patients treated at Seoul National Hospital University between 1996 and 2015 were divided into four 5-year cohorts according to the date of initial diagnosis. Changes in demographic characteristics, drug resistance, drugs used, treatment outcomes and adverse events over time were elucidated. RESULTS: Between 1996 and 2015, 418 patients were treated for MDR-TB: 86 patients between 1996 and 2000, 125 between 2001 and 2005, 123 between 2006 and 2010, and 84 between 2011 and 2015. The proportion of patients with positive acid-fast bacilli sputum (60.5-29.7%, P < 0.001) or cavities on chest radiographs (86.0-40.5%, P < 0.001) decreased over time. Resistance to pyrazinamide, fluoroquinolones, cycloserine and p-aminosalicylic acid decreased. Later-generation fluoroquinolones (77.9-90.5%) and linezolid (0-26.2%) became more frequently prescribed. The treatment success rate increased (45.3-88.1%, P < 0.001); neurological adverse events, including peripheral neuropathy also increased (4.7-13.1%, P = 0.027). CONCLUSION: MDR-TB patients presented with less severe disease and better resistance profiles over time in South Korea, with treatment outcomes improving continuously.

Nutritional deficit as a negative prognostic factor in patients with miliary tuberculosis.

The effects of malnutrition on outcomes in miliary tuberculosis (MTB) are not well described. The aim of the present study was to find predictors for the development of acute respiratory failure (ARF) and survival in MTB patients, focusing on parameters reflecting nutritional condition. Out of the patients from three hospitals who had microbiologically or histopathologically confirmed tuberculosis, 56 patients presenting with typical disseminated pulmonary nodules on radiographs were retrospectively enrolled. A four-point nutritional risk score (NRS) was defined according to the presence of four nutritional factors: low body mass index (BMI; <18.5 kg x m(-2)), hypoalbuminaemia (<30.0 g x L(-1)), hypocholesterolaemia (<2.33 mmol x L(-1)) and severe lymphocytopenia (<7 x 10(5) cells x L(-1)). The male to female ratio was 1:3. ARF developed in 25% of patients (14 out of 56), with a 50% fatality rate. A high NRS (> or =3 points) was an independent risk factor for the development of ARF and fatality. In 90-day survival analysis, ARF, severe lymphocytopenia, hypocholesterolaemia, low BMI and higher NRS were risk factors for poor outcome. In multivariate analysis, only high NRS was an independent risk factor for 90-day survival rate in patients with MTB. A high nutritional risk score was a good predictor of poor outcome in miliary tuberculosis patients. Additional approaches to recover the nutritional deficits may become a focus in future management of miliary tuberculosis.

Predictors of persistent airway stenosis in patients with endobronchial tuberculosis.

SETTING: The university and municipal hospitals in Seoul, Korea. OBJECTIVE: To evaluate the predictors of persistent airway stenosis following anti-tuberculosis chemotherapy in patients with endobronchial tuberculosis (TB). DESIGN: Diagnosis of TB was confirmed by microbiology or histopathology. Bronchoscopic examinations revealed that patients had endobronchial lesions compatible with endobronchial TB. Study subjects had at least one follow-up bronchoscopy to evaluate their treatment response. Treatment response was determined by changes in the degree or extent of airway stenosis between the first and last bronchoscopic examinations. RESULTS: Sixty-seven subjects were recruited retrospectively from Seoul National University Hospital and Seoul National University Boramae Hospital. Persistent bronchostenosis occurred in 41.8% of the patients. In multivariate regression analysis, age >45 years (OR 3.65), pure or combined fibrostenotic subtype (OR 5.54) and duration from onset of chief complaint to the initiation of anti-tuberculosis chemotherapy >90 days (OR 5.98) were identified as independent predictors of persistent airway stenosis. Oral corticosteroids (prednisolone equivalent >or=30 mg/d) did not reduce the frequency of persistent airway stenosis. CONCLUSION: Early diagnosis and early administration of anti-tuberculosis chemotherapy before involvement of the deeper airways is important to prevent the development of unwanted sequelae of bronchostenosis.

Decreased phosphorylation of STAT-1, STAT-4 and cytokine release in MDR-TB patients with primary resistance.

SETTING: We recently showed that treatment failure rate was higher among multidrug-resistant tuberculosis (MDR-TB) patients without a previous history of tuberculosis (TB) treatment, or so-called 'primary resistance'. OBJECTIVE: To investigate the phosphorylation levels of signal transducers and activators of transcription-1 (STAT-1) and STAT-4 and the subsequent cytokine release as a possible cause of a poor prognosis in MDR-TB patients with primary resistance. DESIGN: Ten patients with successfully treated pulmonary TB without resistance, 12 MDR-TB patients with acquired resistance and 10 MDR-TB patients with primary resistance were enrolled. After 24 h stimulation of peripheral blood mononuclear cells (PBMC) with interferon-gamma (IFN-gamma), interleukin-12 (IL-12), purified protein derivative (PPD), or lysate of Mycobacterium tuberculosis, flow cytometric analysis of intracellular pSTAT-1 and pSTAT-4 were performed and secretion of IFN-gamma, IL-12p40 and tumour necrosis factor-alpha (TNF-alpha) was measured in culture supernatant. RESULTS: The mean fluorescent intensities of pSTAT-1 and pSTAT-4 in PBMC of MDR-TB patients with primary resistance decreased on stimulation of IFN-gamma, PPD or lysate of M. tuberculosis when compared with patients with acquired resistance. In addition, secretion of IFN-gamma, IL-12p40 and TNF-alpha in these patients decreased on various stimuli. CONCLUSION: Decreased phosphorylation of STAT-1, STAT-4, and of subsequent cytokine release, might be associated with a poor prognosis in MDR-TB patients with primary resistance.

Isolation and characterization of bacteriocin-producing bacteria from the gastrointestinal tract of broiler chickens for probiotic use.

AIMS: To isolate and characterize the bacteriocin-producing bacteria (BPB) from the gastrointestinal tract of broiler chickens for probiotic use. METHODS AND RESULTS: In total, 291 bacterial strains were isolated from broilers and screened for bacteriocin-producing ability. The bacteriocins produced by Enterococcus faecium SH 528, Ent. faecium SH 632 and Pediococcus pentosaceus SH 740 displayed inhibitory activity against pathogens including Clostridium perfringens and Listeria monocytogenes. Activity of the bacteriocins remained unchanged after 30 min of heat treatment at 60 degrees C or exposure to organic solvents, but diminished after treatment with proteolytic enzymes. PCR was used to detect the structural genes enterocin A and B in SH 528, enterocin L50 and P in SH 632, and pediocin PA-1 in SH 740. Most of them were resistant to 0.5% bile salts and remained viable after 2 h at pH 3.0. Ent. faecium SH 528 exhibited the highest amylase activity among the strains tested. CONCLUSIONS: We selected Ent. faecium SH 528 and SH 632 and Ped. pentosaceus SH 740 by probiotic selection criteria including inhibition activity against pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: The isolated BPB could potentially be used in the poultry industry as probiotics to control pathogens.

Isolation and partial characterization of a bacteriocin produced by Pediococcus pentosaceus K23-2 isolated from Kimchi.

AIMS: Screening and partial characterization of a bacteriocin produced by Pediococcus pentosaceus K23-2 isolated from Kimchi, a traditional Korean fermented vegetable. METHODS AND RESULTS: A total of 1000 lactic acid bacteria were isolated from various Kimchi samples and screened for the production of bacteriocin. Pediocin K23-2, a bacteriocin produced by the Pediococcus pentosaceus K23-2 strain, showed strong inhibitory activity against Listeria monocytogenes. The bacteriocin activity remained unchanged after 15 min of heat treatment at 121 degrees C or exposure to organic solvents; however, it diminished after treatment with proteolytic enzymes. The bacteriocin was maximally produced at 37 degrees C, when the pH of the culture broth was maintained at 5.0 during the fermentation, although the optimum pH for growth was 7.0. The molecular weight of the bacteriocin was about 5 kDa according to a tricine SDS-PAGE analysis. CONCLUSIONS: Pediococcus pentosaceus K23-2 isolated from Kimchi produces a bacteriocin, which shares similar characteristics to the Class IIa bacteriocins. The bacteriocin is heat stable and shows wide antimicrobial activity against Gram-positive bacteria, especially L. monocytogenes. SIGNIFICANCE AND IMPACT OF THE STUDY: Pediocin K23-2 and pediocin K23-2-producing P. pentosaceus K23-2 could potentially be used in the food and feed industries as natural biopreservatives, and for probiotic application to humans or livestock.

Aetiologies and predictors of pulmonary cavities in South Korea.

OBJECTIVE: To identify the aetiologies of pulmonary cavities and the clinical predictors of cavities of mycobacterial origin. SETTING: A tertiary referral hospital in South Korea, where the prevalence of tuberculosis (TB) is intermediate. DESIGN: A retrospective review of clinical records and radiographic examinations of patients presenting pulmonary cavities on simple chest radiograph between January and December 2005. RESULTS: Of 131 patients enrolled with pulmonary cavities, 66 (50.4%) had cavities of mycobacterial origin. Age <50 years (P = 0.04) and largest cavity located in the upper lobes (P = 0.04) increased the likelihood that the cavities were of mycobacterial origin. Conversely, history of malignancy (P = 0.02), lesions confined to one lobe (P = 0.02) and multiple enlarged mediastinal lymph nodes (P = 0.03) suggested a non-mycobacterial cause. CONCLUSION: Mycobacterial infection accounted for half of the cavitary lesions identified in this study. In older patients with a history of malignancy, non-nodular infiltration, lesions confined to one lobe and with multiple lymphadenopathy, diseases not caused by mycobacteria should be considered.

Determinants of diagnostic bronchial washing in peripheral lung cancers.

OBJECTIVE: To establish clinical determinants affecting the diagnostic yield of bronchial washing. SETTING: We performed bronchial washing in 241 consecutive patients with bronchoscopically invisible lung tumours. Of these, 150 patients known to have lung cancer were enrolled for the final analysis. DESIGN: A multi-centre study. RESULTS: Bronchial washing provided a diagnosis of lung cancer in 30 of the 150 patients (20%). Tumour size > or = 3 cm (P = 0.005), the location of the tumour within 8 cm of the carina (P = 0.003), and exposed type bronchus sign of tumour (P < 0.001) were factors affecting diagnostic bronchial washing for bronchoscopically invisible lung cancers. However, multivariate logistic regression revealed that exposed type bronchus sign was the sole determinant (OR 19.22, 95% CI 4.23-87.46, P < 0.001). CONCLUSION: Bronchial washing is a useful procedure for the diagnosis of bronchoscopically invisible lung cancers. As the tumour-bronchus relationship is the most important determinant of a diagnostic yield, the routine use of bronchial washing should be considered for tumours with exposed type bronchus sign.

The mechanical behaviour of chondrocytes predicted with a micro-structural model of articular cartilage.

The integrity of articular cartilage depends on the proper functioning and mechanical stimulation of chondrocytes, the cells that synthesize extracellular matrix and maintain tissue health. The biosynthetic activity of chondrocytes is influenced by genetic factors, environmental influences, extracellular matrix composition, and mechanical factors. The mechanical environment of chondrocytes is believed to be an important determinant for joint health, and chondrocyte deformation in response to mechanical loading is speculated to be an important regulator of metabolic activity. In previous studies of chondrocyte deformation, articular cartilage was described as a biphasic material consisting of a homogeneous, isotropic, linearly elastic solid phase, and an inviscid fluid phase. However, articular cartilage is known to be anisotropic and inhomogeneous across its depth. Therefore, isotropic and homogeneous models cannot make appropriate predictions for tissue and cell stresses and strains. Here, we modelled articular cartilage as a transversely isotropic, inhomogeneous (TI) material in which the anisotropy and inhomogeneity arose naturally from the microstructure of the depth-dependent collagen fibril orientation and volumetric fraction, as well as the chondrocyte shape and volumetric fraction. The purpose of this study was to analyse the deformation behaviour of chondrocytes using the TI model of articular cartilage. In order to evaluate our model against experimental results, we simulated indentation and unconfined compression tests for nominal compressions of 15%. Chondrocyte deformations were analysed as a function of location within the tissue. The TI model predicted a non-uniform behaviour across tissue depth: in indentation testing, cell height decreased by 43% in the superficial zone and between 11 and 29% in the deep zone. In unconfined compression testing, cell height decreased by 32% in the superficial zone, 25% in the middle, and 18% in the deep zones. This predicted non-uniformity is in agreement with experimental studies. The novelty of this study is the use of a cartilage material model accounting for the intrinsic inhomogeneity and anisotropy of cartilage caused by its microstructure.

Lack of association between COPD and transforming growth factor-beta1 (TGFB1) genetic polymorphisms in Koreans.

OBJECTIVE: Many genetic variations have been suggested as genetic risk factors for the development of chronic obstructive pulmonary disease (COPD), including single nucleotide polymorphisms in the transforming growth factor-beta1 (TGFB1) gene. We attempted to elucidate the association between TGFB1 genetic polymorphisms and COPD among Koreans. DESIGN: The genotypes of 102 male patients with COPD and 159 volunteers with similar distributions of age, sex and smoking intensity, as well as normal pulmonary function, were determined for three previously associated TGFB1 single nucleotide polymorphisms (SNPs), -10807G/A (rs2241712) and -509T/C (rs1800469), located in or near the promoter, and 29T/C (rs1982073), located in exon 1 of the TGFB1 gene. RESULTS: No significant associations between COPD and the three TGFB1 SNPs could be identified. In addition, the haplotypes composed of three TGFB1 SNPs were not associated with the presence of COPD. CONCLUSION: These results differ from previous reports involving Caucasians, and might reflect racial differences in the pathogenesis of COPD.

Simultaneous treatment of sewage sludge and food waste by the unified high-rate anaerobic digestion system.

This study aimed to evaluate the performance of the unified high-rate anaerobic digestion (UHAD) system treating co-substrate of sewage sludge and food waste. A 24-hr operating sequence consisted of four steps including fill, react, settle, and draw. The effects of co-substrate and organic loading rate (OLR) on the performance were investigated to verify the system applicability. In each OLR, the UHAD system showed higher CH4 recovery (> 70%), CH4 yield (0.3 L CH4/g VSadded) and CH4 production rate (0.6 L CH4/L/d) than the control system. In the specific methanogenic activity (SMA) tests on thermophilic biomass of the UHAD system, the average SMA of acetate (102 mL CH4/gVSS/d) was much higher than those of butyrate (85 mL CH4/g SS/d) and propionate (42 mL CH4/gVSS/d). It was demonstrated that the UHAD system for co-digestion resulted in higher methane yield and methane production rate due to sequencing batch operation, thermophilic digestion, and co-digestion. The enhanced performance could be attributed to longer retention time of active biomass, faster hydrolysis, higher CH4 conversion rate, and balanced nutrient conditions of co-substrate in the UHAD system. Consequently, this optimized unification could be a viable option for the simultaneous treatment of two types of OFMSW with high stability.