Transcutaneous auricular vagus nerve stimulation would be an alternative to implantable cervical vagus nerve stimulation in some situation.

Implantable cervical vagus nerve stimulation (iVNS) is a representative and promising neuromodulation. However, the invasive nature restricts its application. Traditional auricular acupuncture treatment has a long history. The auricular branch of the vagus nerve (ABVN) is a branch on the surface of the ear. Some studies demonstrates that transcutaneous auricular vagus nerve stimulation (taVNS) would achieve similar effects as iVNS. TaVNS and iVNS share a common anatomical basis and acting mechanism. In this article, we made a comparison between iVNS and taVNS in indications and efficacy. The recent studies have revealed similar clinical efficacy of taVNS, taVNS would expand the indication of iVNS. High-quality clinical evidences are needed before taVNS become be an alternative of iVNS.

Analysis of Animal Models of Cervical Spondylotic Radiculopathy Based on Characteristics of Clinical Symptoms of Chinese and Western Medicine / 中国实验方剂学杂志

With the acceleration of social rhythm， the progress of science and technology， and the increase of the number of phubbers， the incidence of cervical degenerative diseases is also increasing year by year. Cervical spondylotic radiculopathy（CSR）， as one of the diseases induced by cervical degeneration， has seriously affected people's quality of life and physical and mental health. Traditional Chinese medicine（TCM） is effective in the treatment of CSR， but the theoretical and basic experimental evidence is not sufficient， and the current formulation standard of animal model is not unified. Therefore， based on the clinical guidelines of Chinese and Western medicine for CSR and the characteristics of the disease and syndrome， the author systematically summarized and analyzed the existing animal models， and found that the existing models of microvascular clamp nerve root compression method had a poor agreement with the the Chinese and Western medical guidelines， while the modeling methods of spinal canal insertion， autologous bone insertion compression， stainless steel column compression， and fixed frame cervical degeneration reflected a high degree of agreement in the Western medical guidelines. However， the Chinese medical diagnostic criteria were poorly matched. This indicates that the existing animal models of this disease show few TCM syndrome elements， and lack information collection and evaluation in animal behavioral evaluation similar to the four diagnoses of TCM. In conclusion， this paper aims to systematically evaluate the current status of animal model establishment of CSR based on the concept of combination of disease and syndrome， so as to provide a theoretical basis for the model establishment of CSR that is more consistent with clinical characteristics and symptoms of Chinese and Western medicine.

Twelve-section ultrasonic screening diagnosis method for neonatal complex congenital heart disease in primary hospitals at county level / 中华围产医学杂志

Objective:To investigate the feasibility of "twelve-section ultrasonic screening diagnosis method" in screening for neonatal complex congenital heart disease (CHD) in primary hospitals.Methods:This is a prospective study. A total of 71 580 newborns were screened for CHD using the "twelve-section ultrasonic screening diagnosis method" from four pilot units in Hebei province, which were Bo'ai Hospital of Huanghua Development Zone, Traditional Chinese Medicine Hospital of Fengning County, Maternity & Child Healthcare Hospital of Tang Country, and Maternity & Child Healthcare Hospital of Rongcheng Country, from November 2015 to December 2019. Another 262 children with CHD were enrolled, including 39 with complex CHD. These cases received ultrasonography at four pilot units above and then were transferred to CHD Screening Diagnosis and Treatment Center of Hebei Children's Hospital (our center) prior to the implementation of "twelve-section ultrasonic screening diagnosis method" from June 2012 to June 2014, who were all confirmed by surgery. Set the diagnosis results of our center as the gold standard, the sensitivity, specificity, and diagnostic consistency rate in screening for complex CHD cases were calculated. Receiver operating characteristic (ROC) analysis and Chi-square test were used to compare and analyze the sensitivity for screening neonatal complex CHD before and after implementing the method. The screening results of complex CHD after implementing the method between the pilot units and our center as well as between the four pilot units were compared and analyzed using Chi-square test. Results:A total of 553 (0.77%) CHD cases were detected by the "twelve-section ultrasound screening diagnosis method", including 66 cases of complex CHD and 487 cases simple CHD. Among the cases screened using the method, there were three false negative cases (one case with total anomalous pulmonary venous drainage, one with abnormal coronary artery originating from pulmonary artery, and one with atresia of distal to the left subclavian artery, aortic arch and left aortic arch of double-arch), one false positive case (false echo loss of aortopulmonary septal that was misdiagnosed as aortopulmonary septal defect), five cases of misdiagnosis (one common pulmonary venous atresia case that was misdiagnosed as total anomalous pulmonary venous drainage, one persistent stenosis of the fifth aortic arch that was misdiagnosed as coarctation of aorta, one pulmonary artery sling that was misdiagnosed as absence of left pulmonary artery, one severe coarctation of aorta that was misdiagnosed as interruption of aortic arch, and one aortic isthmus atresia that was misdiagnosed as coarctation of aorta), and all were complex CHD cases. A total of 68 cases (12.3%) of complex CHD were confirmed by our center. The overall sensitivity, specificity, and diagnostic consistency rate of screening were 95.6% (65/68), 99.8% (484/485), and 86.8% (59/68), respectively and the area under ROC curve was 0.98. Before the implementation, the overall sensitivity, specificity, and diagnostic coincidence rates of ultrasonic screening for complex CHD were 69.2%(27/39), 95.5%(213/223), and 61.5% (24/39), respectively, and the area under ROC curve was 0.82. The sensitivity of complex CHD screening was significantly increased after implementing the method ( χ2=14.28, P<0.05). There was no significant statistical significance in the sensitivity for screening complex CHD after the implementation between the pilots and our center or between the four pilots (all P>0.05). Conclusions:"Twelve-section ultrasonic screening diagnosis method" is suitable for the screening of neonatal complex CHD in hospitals at the county level. However patients with some special types of complex CHD are recommended to be transferred for a more accurate diagnosis.

Application and Prospect Analysis of Preparation Technology in Improving Antibacterial Activity of Traditional Chinese Medicine / 中国实验方剂学杂志

Pathogenic bacterial infection is one of the main clinical symptoms. Antibiotics are widely used in clinical practice to inhibit or kill the bacteria， fungi and other pathogenic microorganisms. However， with the massive use of antibiotics， drug-resistant strains continue to appear that make the antibacterial situation is becoming increasingly severe. Due to the advantages of multiple targets， multiple pathways and multiple components， traditional Chinese medicine （TCM） have gradually attracted more attention and were used in antibacterial treatment. However， some antimicrobial TCM have problems such as low solubility， poor stability， and low bioavailability. Improving and enhancing the antibacterial activity of TCM through preparation technology is one of the effective solutions. Based on this， two aspects of unilateral antibacterial TCM preparation technology and combination antibacterial preparation technology are introduced， including inclusion technology， nanotechnology， electrospinning， 3D printing and others. Distinctive features and specific application effects of these preparation technologies are explained firstly， and then their advantages and disadvantages are compared and analyzed. The review can be a useful reference for improving the antibacterial activity of TCM.

Clinical observation on cluster acupuncture at scalp points combined with exercise therapy in treatment of limb spasm after stroke / 中国针灸

OBJECTIVE@#To observe the clinical effect of cluster acupuncture at scalp points in treating limb spasm after stroke on the basis of conventional exercise therapy.@*METHODS@#A total of 72 patients with limb spasm after stroke were randomly divided into an observation group (36 cases, 5 cases dropped off) and a control group (36 cases, 6 cases dropped off). The control group was treated with exercise therapy. In the observation group, on the basis of the control group, penetrating technique of acupuncture was exerted at Qianding (GV 21) to Baihui (GV 20), Xinhui (GV 22) to Qianding (GV 21), etc. once a day, 5 days a week for 4 weeks. Before and after treatment, the changes of the modified Ashworth scale (MAS), simplified Fugl-Meyer motor assessment (FMA), and modified Barthel index (MBI) scores of the two groups were compared.@*RESULTS@#After treatment, the MAS scores of upper and lower limbs in the two groups were lower than before treatment (P<0.05), and those in the observation group were lower than the control group (P<0.05). After treatment, the scores of FMA and BMI in the two groups were higher than before treatment (P<0.05), and the score of MBI in the observation group was higher than the control group (P<0.05).@*CONCLUSION@#On the basis of conventional exercise therapy, cluster acupuncture at scalp points can reduce the spasm, improve motor function and activities of daily living in patients with limb spasm after stroke.

Quality Control Test of Transcranial MRI-guided Focused Ultrasound Treatment System before Surgery / 中国医疗器械杂志

OBJECTIVE@#To investigate the pre-treatment preventive maintenance and quality control procedure of MRI system and transcranial MRI-guided focused ultrasound (TcMRgFUS) treatment system by monitoring quality control of these two systems.@*METHODS@#The general performance index and image quality control index of MRI system, as well as the quality assurance program of TcMRgFUS EXABLATE 4000 system were tested and recorded.@*RESULTS@#The general performance index and image quality control index of MRI system met requirements.@*CONCLUSIONS@#Through system detection, the system performance could be monitored, ensuring the accuracy and safety of surgery.

Application of oscillating chemical fingerprint technology combined with mathematical analysis method in quality control analysis of traditional Chinese medicine and food / 中国中药杂志

Oscillating chemical fingerprint is a nonlinear dynamic fingerprint technology that reflects the overall redox activity of the entire system based on potential-time changes in multi-stage chemical reactions. This article summarizes the application of oscillating chemical fingerprint technology combined with mathematical analysis method in the qualitative and quantitative analysis of traditional Chinese medicine and food in recent years, including similarity analysis, principal component analysis, cluster analysis and other qua-litative analysis methods, as well as linear, logarithmic, exponential, polynomial, multivariate analysis and other quantitative analysis methods, so as to provide meaningful information for further quality control analysis of the oscillation chemical fingerprint technology in the field of traditional Chinese medicine and food.

Study on potential hepatotoxicity of main monomers of Polygonum multiflorum based on liver micro-tissue / 中国中药杂志

In this study, we aimed to establish a rat liver micro-tissue evaluation system to evaluate the hepatotoxicity of the main monomers in Polygonum multiflorum. Rat primary hepatocytes were isolated and purified by two-step in situ perfusion method to prepare hepatic parenchymal cells. The ultra-low adsorption plate and the inverted model were used to establish an in vitro hepatotoxicity evaluation system. After the system was established, the main monomer components(monanthone with emodin type, rhein, emodin, emodin-8-O-β-D-glucopyranoside, physcion) of P. multiflorum were selected for in vitro hepatotoxicity evaluation. This study showed that the primary cells of the liver can form liver micro-tissues in the low adsorption plate method and the mold perfusion method, with good liver structure and function, which can be used to evaluate the hepatotoxicity of the drug to be tested after long-term administration. The five monomers to be tested in P. multiflorum can significantly affect the proliferation of primary liver micro-tissues in rats in a dose-and time-dependent manner. The hepatotoxic effects were as follows: monanthone with emodin type > rhein > emodin > emodin-8-O-β-D-glucopyranoside > physcion. The results suggested that the emodin-type monoterpene and rhein might be the potential hepatotoxic components, while the metabolites of emodin-8-O-β-D-glucoside and emodin methyl ether showed more toxic risks. The rat primary hepatocyte micro-tissue model system established in this experiment could be used to achieve long-term drug administration in vitro, which was consistent with the clinical features of liver injury caused by long-term use of P. multiflorum. The experimental results provided important information and reference on the clinical application and toxic component of P. multiflorum.

Report on the disciplinary development of acupuncture-moxibustion and in 24 colleges and universities of TCM in China from 2013 to 2017 / 中国针灸

The questionnaire of was issued to 24 colleges and universities of TCM in China. The questionnaire systematically investigated the recent disciplinary development of acupuncture-moxibustion and from the aspects of specialty construction, student enrollment, faculty construction, personnel training quality, teaching quality and scientific research results. As a result, from 2013 to October of 2017, the above aspects in 24 colleges and universities of TCM in China showed an increasing trend year by year. Based on this survey, this report aimed to fully reflect the disciplinary development of acupuncture-moxibustion and in China, which could analyze the current situation for education departments and training units, and provide data reference and support for acupuncture and discipline to become a first-class discipline.

Effects of Acupuncture on Inflammation in Prefrontal Cortex of Vascular Dementia Rats / 中国中医药信息杂志

Objective To observe the effects of acupuncture on TLR4, inflammation factors IL-1β and IL-6 expressions in the prefrontal cortex of vascular dementia (VD) rats; To investigate the brain protective mechanisms of acupuncture. Methods A total of 50 rats were randomly divided into sham-operation group, model group, acupuncture group, and placebo-acupuncture group. The animal model of VD was replicated by permanent bilateral common carotid artery occlusion (2VO) in rats. Acupuncture was performed at three days after surgery, once daily for two weeks. Morris water maze was used to test the cognitive function. The expressions of Iba1 and TLR4 were assessed by immunohistochemical method. Inflammation factors IL-1β and IL-6 mRNA expressions were tested by RT-PCR. Results Compared with sham-operation group, the model group rats showed impaired spatial learning and memory ability, and expression of Iba1, TLR4, and IL-1β, IL-6 increased. Compared with the model group, the spatial learning and memory abilities of the acupuncture group were improved, and the expression of Iba1, TLR4 and IL-1β, IL-6 in the prefrontal cortex decreased. These effects were not found in the placebo-acupuncture group. Conclusion The effect of acupuncture may be achieved by inhibiting microglia activate, decreasing the expressions of TLR4, IL-1β and IL-6 in the prefrontal cortex, resulting in improving spatial learning and memory ability of VD rats.

Effects of siRNA interference combined with hyperbaric oxygen treatment on cerebral edema and apoptosis in the brain tissue of rats after hemorrhage / 中华老年医学杂志

Objective To examine the effects and mechanisms of siRNA targeting aquaporin 4 (AQP 4) in combination with hyperbaric oxygen therapy(HBO) on cerebral edema and apoptosis in the brain tissue of rats after hemorrhage.Methods Rats were randomly divided into four groups,the control group,the hyperbaric oxygen group,the AQP-4 siRNA group and the combination therapy group (24 rats).Thrombin Ⅶ was injected into the caudate nucleus to establish the hemorrhage model.Construction of siRNA targeting aquaporin 4 was conducted.The mRNA expression of AQP-4 was detected by RT-PCR at day 3.Changes in brain moisture and blood-brain barrier perme ability were measured by a wet/dry weight method and Evans blue fluorometry.The nerve cell apoptosis rate was analyzed by Annexin V andTdT-mediated dUTP-biotin nick end labeling (TUNEL).The expression of proteins including AQP-4,MMP-2,MMP-9,Bcl-2 and caspase-3 was detected by Western Blotting.All the animals were given a score for their nerve function at day 3.Results AQP-4 siRNA treatment obtained better effects than HBO in decreasing the brain edema leveland silencing AQP-4 mRNA(P＜0.05)while,the combination therapy group achieved the best results(P＜ 0.05).Compared with the control group,the percentage of apoptotic cells decreased in all the three treatment groups,with the most marked decrease observed in the combination treatment group(4.24± 0.04)％(F=13.76,P=0.001).The expression of AQP-4,MMP-2,MMP-9 and caspase-3 was lower (P＜0.05) and the expression of Bcl-2 was higher(P＜0.01)in the combination treatment group than in the other three groups.Compared with the control group,all the other three groups received better scores on nerve function defect evaluation at day 3 after hemorrhage(P＜0.05),with the combination treatment group again achieving the most favorable score (4.7 ± 1.1) (F=7.21,P =0.013).Conclusions Targeted siRNA interference combined with hyperbaric oxygen can effectively reduce cerebral edema after cerebral hemorrhage,inhibit neuronal apoptosis and promote neuron function recovery.The underlying mechanisms may be related to down-regulation of AQP-4,MMP 2,MMP-9 and caspase-3 expression and up-regulation of Bcl-2 expression.

Review of the medicinal value aboutRhamnusL. extract / 国际中医中药杂志

RhamnusL., a kind of traditional Chinese medicine, is mainly used to treat some diseases as a supplementary component in the formula. This paper, reviewed its potential medicinal value in the antibacterial activity, antioxidantactivity, anti-allergic activity and anti-tumor activity.

Comparative analysis of chemical constituents, antimicrobial and antioxidant activities of ethylacetate extracts of Polygonum cuspidatum and its endophytic actinomycete, Streptomyces sp. A0916 / 中国天然药物

The present study investigated the chemical composition of ethylacetate extracts from an endophytic actinomycete Streptomyces sp. A0916 and its host Polygonum cuspidatum. A comparative analysis of the antimicrobial and antioxidant properties of the extracts was also conducted. 32 compounds of P. cuspidatum and 23 compounds of Streptomyces sp. A0916 were isolated and identified by GC/MS. Antimicrobial activities of the extracts were evaluated using eight microbial strains (3 Gram-positive bacteria, 3 Gram-negative bacteria, and 2 fungi). The Streptomyces sp. A0916 extracts showed a wide range of antimicrobial activities and presented greater antimicrobial effectiveness than the P. cuspidatum extracts. The minimum inhibitory concentration (MIC) of Streptomyces sp. A0916 extracts against the ampicillin-resistant strain Enterococcus faecium SIIA843 was 32 μg·mL(-1). Furthermore, the extracts had greater antimicrobial effect against Gram-positive bacteria than Gram-negative bacteria. Finally, the antioxidant activity of the Streptomyces sp. A0916 extracts was equal to that of the P. cuspidatum extracts. In conclusion, our results suggest that the endophytic actinomycetes of the medicinal plants are an important source of bioactive substances.

Gu’s Surgery Department’s Three Generations in Treatment of Plasma Cell Mastitis / 浙江中医药大学学报

Objective] Summarize the experience of diagnosis and treatment of plasma cell mastitis by Gu ’s surgery department. [Method] By collecting medical records, from the teachers, pathogenesis, to summarize the inheritance and development of diagnosis and treatment of plasma cell mastitis by Gu ’s surgery department three generations, according to the present situation, analysis of the problems existing in the treatment of the disease. [Results] The disease was first discovered and reported by Dr.Gu Bohua in the domestic.Gu’s surgery department gradually gropes for a set of solution method in treatment of plasma cell mastitis after three generations from the treatment based on the external therapies in the initial, to later, internal and external therapies, at present based on the internal therapies. Clinical studies have found that the internal and external therapies have advantages of high cure rate, short treatment time, but the scar is larger, while the internal therapies in the long treatment cycle achieve the same cure rate, but the scar is smaller, less expensive. But the exploration of the cause of the disease, diagnosis and standardized treatment is still fraught with problems. [Conclusion]Developing by three generations, Gu ’s surgery department provides a more complete mentality and pragmatic value in treating plasma cell mastitis.

Comparative analysis of trace elements in five marine-derived shell TCM using multivariate statistical analysis / 中国中药杂志

A comparable study were carried out by determination of trace elements on five marine-derived shell traditional Chinese medicine (TCM) (Ostreae Concha, Haliotidis Concha, Margaritifera Concha, Meretricis Concha, and Arcae Concha), which were recorded in the Chinese Pharmacopoeia (2010 version). Seven trace elements in 51 batches of this type of shell TCM were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS), combined with principal component analysis (PCA) methods. The content of element Se, which exhibited significant differences among different drugs, could be used as a key element to distinguish this type of drugs. Meanwhile, the contents of elements Co, Cu, Mo, and Ba in Haliotidis Concha, Co and As in Margaritifera Concha, Mo and As in Meretricis Concha, Mo, As, and Ba in Arcae Concha, and Zn in Meretricis Concha were relatively stable. In the PCA plot, Arcae Concha and Meretricis Concha could be efficiently distinguished from Ostreae Concha together with Haliotidis Concha, and Margaritifera Concha. The results also showed a correlation with their medicinal function. In conclusion, trace elements in marine-derived shell TCM could not be neglected for their quality control.

Effects of guizhi fuling capsule on sex hormone levels and breast issue morphology of mammary gland hyperplasia model rats / 中国中药杂志

<p><b>OBJECTIVE</b>To research the effects of Guizhi Fuling capsule on sex hormones levels in blood serum and breast issue morphology of hyperplasia of mammary glands model rats.</p><p><b>METHOD</b>The unpregnancy SD rat models of hyperplasia of mammary glands were established by injecting 0.5 mg x kg(-1) benzoate estradiol. After five weeks doses,the effects of Guizhi Fuling capsule 2.0, 1.0, 0.5 g x kg(-1) and Rupixiao tablet 0.5 g x kg(-1) on the changes of papilla diameter, height and breast issue morphology of the naimal models were explored, and sex hormones levels in blood serum were measured.</p><p><b>RESULT</b>Guizhi Fuling capsule can inhibitnipple swell, improve breast tissue morphology pathological profiles of the animal models, and decrease oestradiol (E2) level and increase progesterone (P) level in blood serum.</p><p><b>CONCLUSION</b>These results suggested that Guizhi Fuling capsule could, improve mammary gland pathological profiles. Regulating sex hormone levels may be its important mechanism for treatment of hyperplasia of mammary glands.</p>

Experimental Observation of Lung Oxidative Stress Injury in Mice Model of Chronic Obstructive Pulmonary Disease Induced by Different Inducers / 世界科学技术-中医药现代化

This study was aimed to observe the intervention effect of oxidation/antioxidation at different time point among mice induced by lipopolysaccharide (LPS) and bleomycin. It provided experimental basis for the establishment of chronic obstructive pulmonary disease (COPD) animal model with qi-deficiency and phlegm-obstructing pattern with inducers mentioned above. A total of 96 mice were randomly divided into the normal control group, bleomycin group, and LPS group, with 32 mice in each group. In the bleomycin group and LPS group, 40 μL of nasal drops were given with bleomycin at the concentration of 3.75 μg/μL or LPS at the concentration of 5 μg/μL, respectively to establish the COPD animal model with qi-deficiency and phlegm-obstructing pattern. On the 1st day, 7th day, 14th day and 28th day after the model establishment, the general status and activities of mice were recorded. And traditional Chinese medicine (TCM) signs such as skin color of the four limbs, skin color under the tongue and color of the tail were also collected when the animal model was sacrificed. At each time point, 8 mice were sacrificed. The lung tissues were removed. And the contents of GSH, MDA, SOD and T-AOC were detected in the homogenate of lung tissues. The results showed that compared with the normal control group, mice in the bleomycin group had slightly dull eyes, dry hair without burnish, upright and fluffy hair, dark purple skin color of the auricle and four claws, tiredness, inactivity, occasional cough, asthma or rapid breathing. The GSH content of lung tissues on the 7th day, 14th day and 28th day was obviously reduced (P< 0.05, or P< 0.01). The MDA, SOD and T-AOC contents on the 1st day, 7th day, 14th day and 28th day were obviously reduced (P< 0.05, or P< 0.01). Compared with the normal control group, mice in the LPS group had slightly dull eyes, soft hair with slight burnish, pale red skin color of the auricle and four claws, tiredness; some mice preferred to gather. Contents of GSH and SOD in lung tissues on the 1st day and 7th day were obviously reduced (P< 0.05, or P< 0.01). Contents of MDA and T-AOC on the 1st day, 7th day and 14th day were obviously reduced (P < 0.05, or P < 0.01). It was concluded that obvious oxidation/antioxidation imbalance started on the 7th day in lung tissues of mice in the bleomycin group. It reduced later on. And the oxidation/antioxidation imbalance continued until the end of the model establishment. Obvious oxidation/antioxidation imbalance started on the 1st day in lung tissues of mice in the LPS group. However, this oxidation/antioxidation imbalance was adjusted back to normal level through time.

Performance of multi-soil-layering system (MSL) treating leachate from rural unsanitary landfills.

The widely spread rural unsanitary landfills in South China pose an environmental threat to water bodies and soil. Although various processing technologies have been utilized for treatment of landfill leachate, their application to the landfills in rural areas is restricted by the availability of skilled professionals and high operation costs. In this experiment, four MSLs with altered soil mixed block (SMB) and different hydraulic load rate (HLR) were applied in the experiment to investigate the treatment of the landfill leachate without aeration or under low aeration supply. The experiment results showed that the improved MSL could effectively treat the chemical oxygen demand (COD), NH(4)-N and P. COD and NH(4)-N removal efficiencies of MSL were 97.4%, 82.4% and 72.0%, 62.0%, respectively under HLRs of 200 and 400L/(m(2)·d) without aeration; COD and NH(4)-N removal efficiencies of M800 and M1600 were 62.3%, 53.4% and 45.3%, 35.3% respectively under intermittent aeration. N removal efficiency was low due to a strong nitrification effect, and the nitrogen removal capacity of the MSL was greatly reduced at the end of the experiment. P removal efficiency of MSL was 75.6 to 91.9% under HLR 200 and 400L/(m(2)·d). The intermittent aeration was helpful to remove the clogging of MSLs, after they were clogged under HLRs of 800 and 1600L/(m(2)·d). MSL is promising as an appealing nitrifying biofilm reactor.