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Introduction There is limited data correlating preoperative mobility limitations with clinical outcomes in bariatric patients. This study uses propensity score matching (PSM) to compare 30-day outcomes between patients with preoperative limited mobility (LM) versus patients without (non-LM). Methods Using the 2016-2018 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database, patients undergoing primary laparoscopic sleeve gastrectomy or gastric bypass were identified. Two cohorts were defined using preoperative LM status. To adjust for confounders, 1:1 PSM was performed using 25 preoperative characteristics, and balance was assessed with standardized mean difference. Preoperative patient demographics and postoperative 30-day outcomes were compared in both matched and unmatched cohorts. Results 453,146 patients were identified, of which 6942 (1.47%) were LM and 464,555 were non-LM. 1:1 PSM matched 6624 LM to 6624 non-LM patients with good balance for all covariates. LM had higher rates of unplanned intubation (0.4% vs 0.7%, P < .01), unplanned admission to ICU (1.4% vs 2.5%, P < .01), readmissions (4.1% vs 4.9%, P = .036), unplanned reoperation (1.5% vs 2.0%, P = .02), and 30-day mortality (0.2% vs 0.5%, P = .02). Complications including acute renal failure, intra/postoperative myocardial infarction, venous thrombosis, and pulmonary embolism were not significantly different between the matched groups. Conclusion After adjusting for confounders, patients with preoperative limited mobility have higher rates of intubation, ICU admission, reoperation, readmission, and mortality. Prudent pre-operative candidate selection, counseling, and risk mitigation strategies are needed when a patient with limited mobility status is being considered for bariatric surgery.

Nonalcoholic steatohepatitis (NASH) is common in patients with obesity. Liver biopsy (LB) can be routinely or selectively performed during bariatric surgery to identify patients with NASH.Patients undergoing bariatric surgery between 2016 and 2020 at our institution were identified. Chart review identified patients undergoing concurrent LB. LB results were compared between patients undergoing routine LB and selective LB. Patient demographics and postoperative outcomes were compared between those who received LB and those who did not (non-LB). In the LB cohort, preoperative characteristics of patients with NASH were compared to those without NASH, and multivariable regression was used to identify predictors of NASH.Two thousand three hundred ninety-three patients were identified, of which 400 (16.7%) had liver biopsies (LB) and 1,993 (83.3%) did not (non-LB). Three hundred thirty LB were performed routinely, and 70 were selective. Compared to selective LB, routine LB identified significantly higher rates of steatosis (83.6% vs. 4.5%, p 0.01), periportal inflammation (67.0% vs. 3.2%, p 0.01), fibrosis (65.8% vs. 2.1%, p 0.01), and NASH (10.9% vs. 1.5%, p 0.01). There were no differences in postoperative complications, blood transfusions, readmissions, or reoperations between LB and non-LB. On multivariable regression, highest BMI 40 (OR 2.85, 95% CI 1.43-5.67) and insulin-dependent diabetes (OR 4.83, 95% CI 1.70-13.69) were associated with a higher odds of NASH, while Black race was associated with lower odds (OR 0.25, 95% CI 0.09-0.65).Routine liver biopsies during bariatric surgery identify higher rates of advanced NAFLD compared to selective biopsies, and can be safely performed without an increased risk of postoperative complications.

Background Incorporation of quality improvement (QI) training is essential to meet the milestones set forth by the Accreditation Council for Graduate Medical Education. However, there is no standardized curriculum. Objective We aimed to create a QI curriculum through the integration of didactics and team-based learning via the completion of resident-led QI projects. Methods An institutional review board–approved QI curriculum consisting of four interactive workshops was developed. The workshops introduced the various components of QI, with a focus on Plan-Do-Study-Act. Anonymous and voluntary precurriculum and postcurriculum surveys were administered during the study period in 2018. Results Fifty surgical residents participated in the curriculum, and four QI projects were completed, with 23 residents completing both precurriculum and postcurriculum surveys. Following the curriculum, residents were more confident in their ability to design a QI project (5.7 ± 2.6 versus 7.1 ± 1.9, P = 0.02), write a problem statement (6.7 ± 2.5 versus 7.8 ± 1.1, P = 0.04), and write an aim statement (6.7 ± 2.6 versus 7.8 ± 1.2, P = 0.04). Residents also improved in perceived ability to lead a QI project (5.6 ± 2.9 versus 6.9 ± 1.9, P = 0.05), knowing the steps to complete a QI project (6.0 ± 2.8 versus 7.4 ± 1.7, P = 0.04), and familiarity with QI terminology (5.6 ± 2.6 versus 7.0 ± 1.9, P = 0.03). Conclusions We found that the curriculum was a success and was well received. In addition, there was an improvement in perceived competency and confidence surrounding some of the steps necessary to complete a QI endeavor.

Immunotherapy such as bevacizumab and pembrolizumab is used to treat an increasing number of malignancies. These medications have been associated with poor wound healing and several gastrointestinal complications, including intestinal perforations in rare cases. We present a unique case of a patient with metastatic cervical cancer on pembrolizumab and recent bevacizumab therapy, presenting with a colonic perforation requiring urgent exploratory laparotomy, in the setting of activeClostridium difficileinfection. She required a second laparotomy shortly after due to fascial dehiscence, where a synthetic absorbable mesh was used for fascial approximation. We review the factors that led to these events and describe the surgical technique used for safe abdominal closure.

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Neuralgia due to a peripheral nerve injury may result in chronic pain, requiring a therapeutic surgical neurectomy. Meanwhile, some neurectomies are performed prophylactically, such as during inguinal mesh removal. Outcomes and risks associated with neurectomies are largely unknown despite consensus panels recommending them.All patients who underwent neurectomy 2013-2020 were analyzed. Data collection included demographics, preoperative symptoms, and postoperative outcomes. Indications for neurectomy were categorized as "therapeutic" if the patient had preoperative neuralgia or "prophylactic" if neurectomy was deemed necessary intra-operatively.66 patients underwent 80 operations and a total of 122 neurectomies. On average, 1.5 neurectomies were performed per operation. Therapeutic neurectomies were performed in 42 (64%) patients and prophylactic in 34 (52%). The most commonly transected nerve was the ilioinguinal nerve. Average preoperative pain score was 5.8/10. On paired analysis, there was a significant reduction in pain after prophylactic neurectomy (2.5 points, p = 0.002) but not after therapeutic neurectomy. None of the nerves transected prophylactically had postoperative neuralgia, whereas 35% of the nerves transected therapeutically resulted in persistent or recurrent neuralgia (p 0.001). To treat this, 21% required only nerve blocks and 9% required ablation or reoperative neurectomy. Three patients had complex regional pain syndrome (CRPS), a severe complication; all three were diagnosed with chronic pain syndrome pre-operatively.We demonstrate that prophylactic neurectomy is largely safe. In contrast, a therapeutic neurectomy had a 35% risk of persistent or recurrent neuralgia, 9% required additional ablative or reoperative neurectomy. Three patients advanced from chronic pain syndrome to CRPS. We recommend the decision to perform a neurectomy be judicious and selective, especially in patients with known chronic pain syndrome. Prior to planning surgical neurectomy, other less invasive modalities should be exhausted and patients should be aware of its risks.

Preperitoneally placed mesh for inguinal hernia repair may require removal to address hernia recurrence, mesh reaction, meshoma, or other chronic pain. These are best approached either laparoscopically or robotically, but there is no consensus on which is the best approach for mesh removal nor are there any studies to evaluate and compare their outcomes.All patients who underwent inguinal mesh removal via laparoscopic and robotic approaches from 2011 to 2020 were analyzed. Data regarding demographics, preoperative, intraoperative, and postoperative outcomes were collected.Over 9 years, 62 patients underwent 24 laparoscopic and 50 robotic operations. Laparoscopic cases had a shorter operative time by a mean of 55 min (p = 0.02). There were no differences in intraoperative complications or postoperative outcomes between the two groups. Patients in both groups showed significant improvement after mesh removal (p = 0.02, p 0.01) within 2 weeks postoperatively and at long-term follow up (p 0.01, p 0.01).It is our experience that both laparoscopic and robotic approaches are viable options for removal of retroperitoneally placed inguinal mesh. Operative time with the laparoscopic approach was significantly shorter than the robotic approach. Patients on average had significant reduction in their preoperative pain, regardless of the approach. Minimally invasive mesh removal is a technically challenging operation, with risk of vascular and nerve injuries regardless of the approach. These findings demonstrate that both modalities are safe and effective with experienced surgeons.

Background The safety profile of bariatric surgery in patients with class I obesity, or body mass index ≥30 and Objective To assess the safety profile of bariatric surgery in patients with class I obesity. Setting The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) data set. Methods The Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program 2015 to 2016 data sets were queried for class I obesity patients who underwent primary bariatric procedures. The 30-day postoperative safety profile, predictors of adverse events, and comparison between Roux-en-Y gastric bypass (RYGB) versus sleeve gastrectomy (SG) were studied. Results A total of 8628 cases with a mean preoperative body mass index of 33.7 ± 1.1 kg/m2 were analyzed: 1838 (21.3%) underwent RYGB, 6243 (72.4%) underwent SG, 530 (6.1%) underwent gastric banding, and 17 (.2%) underwent duodenal switch; 33.9% had diabetes and 75% had hypertension. The composite morbidity rate (defined as presence of any of 24 postoperative adverse events) for the entire cohort was 3.8%, and the serious morbidity rate (presence of any of 9 serious complications) was .7%. The 30-day mortality rate was .05% (4 cases). Presence of chronic kidney disease was found to be associated with higher composite and serious morbidity (composite morbidity: odds ratio 5.1, 95% confidence interval 2.22–11.71; serious morbidity: odds ratio 5.66, 95% confidence interval 1.52–21.14). SG patients had significantly better short-term safety outcomes than RYGB patients. Conclusion Findings from this study, the largest series to date, indicate that bariatric surgery is safe in patients with class I obesity, with very low risk of morbidity and mortality.

Enhanced recovery is a concept that has been embraced by some surgical specialties with resultant improvements in complication rates, readmissions, length of stay, and costs. While bariatric surgery is typically a pathway-driven specialty, there is a large amount of variability regarding perioperative care practices among bariatric surgery programs nationally. Enhanced recovery offers the possibility of decreasing this variability across practice settings by implementing evidence-based protocols that minimize surgical stress, maintain homeostasis, and minimize opioid use in all bariatric surgery programs. Protocols such as this also challenge surgical dogma and practices that are not supported by evidence such as “NPO after midnight,” the use of bowel preps, the use of drains and catheters, and routine imaging studies or prolonged periods without oral intake after surgery. Evidence is emerging to support the safety and effectiveness of specific components of enhanced recovery for this unique population, and, as implementation increases, the field of bariatric surgery will continue to be the leader in quality and patient safety among all surgical specialties.

The American Society for Metabolic and Bariatric Surgery (ASMBS) publishes position statements in response to numerous inquiries made to the society by patients, physicians, society members, hospitals, and others regarding a particular topic relevant to the field. In these statements, available data are summarized, and recommendations for treatment are made based on current knowledge, expert opinion, and published peer-reviewed scientific evidence available at the time. The ASMBS leadership also collaborates with other medical societies to develop and publish practice guidelines that are relevant to the care of the bariatric surgery patient. This chapter summarizes the current position statements of the ASMBS.

174 Background: Racial disparities for gastric cancer are often identified in the literature. Although patients in Asia consistently demonstrate a survival benefit compared to those in the West, Asian patients in the US still retain this advantage, which suggests that tumor biology may be a major factor. The goal of our study is to identify racial differences in patient demographics, tumor biology and treatment for gastric cancer in the United States. Methods: The National Cancer Database was queried from 2006-2016 for patients with a diagnosis of gastric adenocarcinoma. Patient demographics, tumor characteristics, and treatment patterns were compared by patient ethnicity (White, Black, Hispanic, and Asian) with Kruskal-Wallis test and Pearson’s chi-squared test. Kaplan-Meier survival curves used to assess overall survival, and cox regression used to identify independent prognostic factors for survival. Results: 116,717 patients with gastric cancer identified; 78,066 were White, 17,486 were Black, 8,494 were Asian, and 12,671 were Hispanic. White patients were most likely to be older than 70 and have proximal tumors, and least likely to have diffuse type adenocarcinoma. Hispanic and Black patients were most likely to present with metastases. Asian patients were most likely to receive surgery and least likely to receive chemotherapy or radiotherapy. Stage for stage, Asians had the longest median survival, followed by Hispanic, Black, and White patients. Prognostic factors associated with a survival benefit include Asian ethnicity (HR 0.72, 95% CI 0.68-0.74), Hispanic ethnicity (HR 0.76, 95% CI 0.73-0.79), Black ethnicity (HR 0.95, 95% CI 0.93-0.98), private insurance (HR 0.91, 95% CI 0.87-0.96), higher income (HR 0.85, 95% CI 0.82-0.88), treatment at academic center (HR 0.87, 95% CI 0.83-0.91), higher-volume centers (HR 0.90, 95% CI 0.87-0.93), receiving surgery (HR 0.42, 95% CI 0.41-0.43), chemotherapy (HR 0.56, 95% CI 0.55-0.57), and radiation (HR 0.96, 95% CI 0.93-0.98). Conclusions: Treatment differences between Eastern and Western countries for gastric cancer persist between ethnic groups within the United States, with Asian patients retaining a survival benefit. Black and Hispanic patients present with aggressive disease and unfavorable socioeconomic factors that are detrimental to overall survival.

The Zhiluo Formation in the Tarangaole area is a part of the Dongsheng uranium ore-field in the northeast Ordos Basin, China. Uraniferous sandstones from this formation are examined in this study. The type and mode of occurrence of uranium minerals is investigated in detail using an electron probe, α-track etching, energy spectrum, backscattering, a scanning electron microscope, and an experiment for sequential extraction of uranium. The results show that these uranium minerals are mainly composed of coffinite, a small amount of pitchblende, and some minerals containing titanium and uranium. Coffinite closely coexists with pyrite, altered ilmenite or leucoxene, charcoal, biotite and clay minerals. Some coffinite occurs along mineral edges as burrs or fine columns; it also occurs in biotite cleavage cracks with granulars. In addition, some uranium minerals are also observed within grains. α-Track etching shows that adsorbed uranium is either distributed at the edge of the debris or scattered among the grains. The sequential extraction experiment indicates that the proportion of uranium minerals was significantly greater than that of the adsorbed uranium in the samples, with the latter being largely present in pyrite and organic matter. Residual, oxidizable and weak acid-extractable uranium occur in the deposit. Scan-mapping of uranium and titanium reveales that brannerite is almost nonexistent. Strongly altered ilmenite is considered a highly effective aggregating agent for uranium. A large number of altered minerals, including clays, carbonaceous clastics, biotite, pyrite and ilmenite, are widely developed in the uraniferous sandstone, and play a significant role in the complex process of adsorption–reduction–precipitation of uranium. The discovery of pitchblende and two types of coffinite (high-Y and low-Y) are discussed in context with their symbiotic relationship with the altered minerals. It is suggested that the uraniferous sandstone underwent at least two stages of fluid activity.

OBJECTIVE There is no standardized method of communication regarding the arrival of outside hospital (OSH) transfers at our institution. We utilized quality improvement methodologies to enhance sign-out, benefiting both resident workflow and patient care. DESIGN A dynamic census log of pending OSH transfers was created. Total number of OSH transfers (with or without prior notification), time to admission orders, and resident self-reported preparedness in receiving/triaging OSH admissions were measured before and after implementation of the census log tool. SETTING Quaternary referral hospital in Cleveland, Ohio. PARTICIPANTS The census log was made available to General Surgery residents on receiving surgical teams. After the data collection period, it was made available to all residents in the program. RESULTS A total of 93 patients were transferred to receiving surgical teams during our 13-week study period. Resident notification of the OSH transfer prior to patient's arrival increased from 44.7% pre- to 70.3% postimplementation of the tool (p = 0.03). When residents received prior notification of pending transfers, time to place admission orders decreased from 81.2 ± 79.9 minutes to 40.4 ± 36.8 minutes (p = 0.0029). Junior residents’ self-reported preparedness in admitting an OSH transfer did not significantly differ when they received prior notification versus when they did not. In contrast, senior residents’ self-reported higher levels of preparedness in the instances where they received prior notification of a pending transfer. CONCLUSIONS In light of the recent Clinical Learning Environment Review program set forth by the Accreditation Council for Graduate Medical Education, trainees are expected to engage in improvement processes as it relates to patient safety and transitions of care. The development and implementation of our tool demonstrate that quality improvement methodologies can be effectively applied to resident workflow challenges, improving both trainee education and patient care.

Some controversies still exist regarding the genesis of sandstone-type uranium deposits in the northeastern Ordos Basin. Herein, based on boreholes and well logging data, we selected sandstone samples representing different epigenetic alteration environments as the research object and comprehensively utilized polarizing microscopy, scanning electron microscopy, electron probe analysis, elemental analysis, and other test methods to research sandstone genesis. The main altered minerals in the sandstone of this area include limonite, pyrite, achavalite, carbonate, sulfate, clay, and uranium minerals. The complex characteristics of alteration minerals indicate multi-stage fluid mixed mineralization in this area. According to the relationship between the major elements in different types of sand bodies, the components were classified into three groups. The first is the reduction media group, including CaO, MnO, total oxygen carbon (TOC), S, U, and burning loss. The second is the detrital particle group, including SiO2, K2O, and Na2O, and the third contains the clay and volcano component group, including Fe2O3, P2O5, TiO2, FeO, MgO, and Al2O3. Among these, the content of reduction media is positively correlated with uranium enrichment, whereas detrital particles and clay components reflect the influence of alteration on the sand body composition, which indirectly affects the uranium adsorption and precipitation. Through the normalization of rare earth element (REE) chondrites, we find that the distribution patterns of REEs in rocks with different geochemical environments show a fractionation of light and heavy rare earth elements (HREEs), a right-leaning enrichment of light rare earth elements (LREEs), and relatively flat HREE. Further, via the Post Archean Australian Shale (PAAS) normalization, we observe that the mudstone of the Zhiluo Formation exhibits a relatively flat curve, whereas the sandstones have strongly positive Eu anomalies. The difference in REE values for different types of sand bodies indicates that, although all types of rocks have a similar sedimentary environment, their original sediments underwent fluid alterations such as oxidation and reduction. Based on the uranium mineralization evolution history in the study area, the water-rock reaction process and mineral-alteration sequence were determined on the basis of alteration types and elemental concentrations. Our findings provide new insight into the petrological significance, mineralogy, and geochemical composition of uranium deposits in the Ordos Basin.

Familial adenomatous polyposis (FAP) is a hereditary colon cancer syndrome that involves multiple extracolonic organs, including the thyroid. Several studies have estimated the rate of thyroid cancer in FAP to occur at five times the rate of the general population, but no current consensus defines screening for thyroid cancer in this cohort. This study seeks to define the features of benign and malignant thyroid disease in FAP patients, to compare thyroid cancer cases found through screening with those found incidentally, and to propose disease surveillance recommendations.Prospective screening for early thyroid cancer detection with thyroid ultrasound (US) was performed on FAP patients at the time of annual colonoscopy since November 2008. Clinical and US data were reviewed to characterize the observed thyroid nodules. Nonscreening-detected cases (NSD) were found through review of the colon cancer registry database.Eighteen NSD were found, compared with 15 screening-detected (SD) cases, out of 205 total patients screened (Mage=42 years; 55% female). The mean tumor size was larger in the NSD group than the SD group (p=0.04), and they tended to demonstrate more positive lymph nodes and more complications than the SD group. In the screened cohort, at least one thyroid nodule was detected in 106 (51.7%) patients, with 90% of these seen on initial exam. A total of 40/106 (37.7%) patients required fine-needle aspiration biopsy of a dominant nodule (Msize=14 mm), and 28/40 (70%) of these were performed at the first US visit. Suspicious US features were present in 16/40 (40%) patients, including five sub-centimeter nodules. Cytology and/or nodule US was abnormal in 15/205 screened patients, leading to surgery and revealing 14 papillary and one medullary thyroid cancer.Given the age and sex distribution of the screened cohort, this study reveals a higher-than-expected prevalence of both benign and malignant thyroid disease in the FAP population. Additionally, SD cases seemed to consist of smaller-sized cancers that required less radical therapy compared to NSD cases. Since it was found that the initial US in the screening program accounted for the majority of detected nodules (90%) and biopsies (70%), baseline and subsequent thyroid US surveillance is recommended in all FAP patients.

The association between community functional shift and dynamics of genomic DNA composition can be used to identify functionally relevant populations as indicator organisms for systems monitoring. In this work, fingerprinting-based community DNA hybridization was used to monitor community structural dynamics and identify genomic fragments whose abundance shifts were concomitant to changes in COD removal capacity in a reactor. A laboratory-scale anaerobic-anoxic-oxic fixed biofilm system treating coking wastewater was operated with (LR mode) or without effluent recirculation (LNR mode). The contribution to total chemical oxygen demand (COD) removal by the anoxic reactor increased from 4% in LNR mode to 26% in LR mode. Long primer RAPD (randomly amplified polymorphic DNA) community fingerprints of the anoxic reactor also changed most significantly from the one similar to the anaerobic reactor to one similar to the oxic reactor. DNA hybridization revealed one signature band of 2.1 kb shared by the anoxic and oxic reactors in LR, but not LNR mode. Clone library profiling of this band resulted in one predominant 2.1-kb genomic fragment (B3) with no homologous sequences in GenBank. Real-time polymerase chain reaction indicated that copy numbers of B3 in the anoxic reactor under LR mode were 69 times higher than that under LNR mode, concomitant to a significant increase in COD removal capacity in this reactor. The different patterns of distribution of B3 in the laboratory system and a comparable malfunctioning industrial system demonstrated the potential of this genomic fragment as physical markers in systems monitoring. In addition, this genomic fragment may allow sequence-guided isolation of the host microbe.

Structural shifts associated with functional dynamics in a bacterial community may provide clues for identifying the most valuable members in an ecosystem. A laboratory-scale denitrifying reactor was adapted from use of nonefficient seeding sludge and was utilized to degrade quinoline and remove the chemical oxygen demand. Stable removal efficiencies were achieved after an adaptation period of six weeks. Both denaturing gradient gel electrophoresis profiling of the 16S rRNA gene V3 region and comparison of the 16S rRNA gene sequence clone libraries (LIBSHUFF analysis) demonstrated that microbial communities in the denitrifying reactor and seeding sludge were significantly distinct. The percentage of the clones affiliated with the genera Thauera and Azoarcus was 74% in the denitrifying reactor and 4% in the seeding sludge. Real-time quantitative PCR also indicated that species of the genera Thauera and Azoarcus increased in abundance by about one order of magnitude during the period of adaptation. The greater abundance of Thauera and Azoarcus in association with higher efficiency after adaptation suggested that these phylotypes might play an important role for quinoline and chemical oxygen demand removal under denitrifying conditions.

A novel process was developed to repeatedly utilize MgNH(4)PO(4)(.)6H(2)O (MAP) for ammonium removal from wastewater by releasing ammonium in MAP through acid dipping. In acid solutions, ammonium can be released to solution from MAP while MAP was transformed to MgHPO4, which can be used to remove ammonium again. Ammonium-N concentration in acid solutions increased with the decreasing pH and increasing temperature, up to 3.27 x 10(4) Mg/l at 60degreesC and pH 4.8. MAP also dissolved into acid solutions when transformation to (MgHPO4N)-N-.:P, indicating the ratio of MAP transformation to MAP dissolution, was maximum at pH 6.0 and increased with the temperature. N:P was up to 38.8 at 60degreesC and pH 6.0. Recycling experiments were done. Ammonium-N in effluents was lower than 20 mg/l in the first five cycles, which indicates the feasibility of this process. XRD spectra also validate the transformation between MAP and MgHPO4.

Background Cervical hematoma can be a potentially fatal complication after thyroidectomy, but its risk factors and timing remain poorly understood. Methods We conducted a retrospective, case-control study identifying 207 patients from 15 institutions in 3 countries who developed a hematoma requiring return to the operating room (OR) after thyroidectomy. Results Forty-seven percent of hematoma patients returned to the OR within 6 hours and 79% within 24 hours of their thyroidectomy. On univariate analysis, hematoma patients were older, more likely to be male, smokers, on active antiplatelet/anticoagulation medications, have Graves' disease, a bilateral thyroidectomy, a drain placed, a concurrent parathyroidectomy, and benign pathology. Hematoma patients also had more blood loss, larger thyroids, lower temperatures, and higher blood pressures postoperatively. On multivariate analysis, independent associations with hematoma were use of a drain (odds ratio, 2.79), Graves' disease (odds ratio, 2.43), benign pathology (odds ratio, 2.22), antiplatelet/anticoagulation medications (odds ratio, 2.12), use of a hemostatic agent (odds ratio, 1.97), and increased thyroid mass (odds ratio, 1.01). Conclusion A significant number of patients with a postoperative hematoma present >6 hours after thyroidectomy. Hematoma is associated with patients who have a drain or hemostatic agent, have Graves' disease, are actively using antiplatelet/anticoagulation medications or have large thyroids. Surgeons should consider these factors when individualizing patient disposition after thyroidectomy.

Since agricultural water security has been threatened by the serious shortage of water resources in northern China, how to efficiently and reasonably use soil water resources has become one of the research hotspots recently. At Taigu Water Balance Experimental Field of Hydrology and Water Resources Survey Bureau in Shanxi Province, we dynamically monitored the air temperature, soil freeze-thaw depth and soil moisture content within the depth of 100 cm from November 1, 2004 to March 31, 2005. And we found that the temperature fluctuated around 0 °C in winter with daytime temperature above 0, and the night temperature below 0 °C The soil within the depth of 10 cm froze at night and thawed at daytime, and soil water increased. As the air temperature continued to decrease, the freezing front developed downward because of the increase of the soil negative accumulated temperature. The frozen soil layer was thickened gradually and reached 60 cm on February 6th, 2005, then the high moisture zone formed at the depth of 30 to 50 cm and the soil water increased by 15% compared with the data of the before winter; due to water migration to the freezing front, the soil water at the depth of 70 to 80 cm decreased by 17% compared with the data of the before winter. The topsoil experienced several freeze-thaw microcirculations owning to the influence of the air temperature since February 13, 2005, and the frozen soil completely thawed on March 17th. The weather was dry during the freeze-thaw period, so the soil water at the depth of 0 to 10 cm decreased by 13% compared with the data of the before winter; the soil water at the depth of 20 to 60 cm increased by 10% after soil thawed completely. The research results would contribute to reasonable agriculture irrigation and high efficient soil water utilization in winter and spring.

Structural shifts associated with functional dynamics in a bacterial community may provide clues for identifying the most valuable members in an ecosystem. A laboratory-scale denitrifying reactor was adapted from use of non-efficient seeding sludge and was utilized to degrade quinoline and remove the chemical oxygen demand. Stable removal efficiencies were achieved after an adaptation period of six weeks. Both denaturing gradient gel electrophoresis profiling of the 16S rRNA gene V3 region and comparison of the 16S rRNA gene sequence clone libraries (LIBSHUFF analysis) demonstrated that microbial communities in the denitrifying reactor and seeding sludge were significantly distinct. The percentage of the clones affiliated with the genera Thauera and Azoarcus was 74% in the denitrifying reactor and 4% in the seeding sludge. Real-time quantitative PCR also indicated that species of the genera Thauera and Azoarcus increased in abundance by about one order of magnitude during the period of adaptation. The greater abundance of Thauera and Azoarcus in association with higher efficiency after adaptation suggested that these phylotypes might play an important role for quinoline and chemical oxygen demand removal under denitrifying conditions.