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Abstract Background Lymphadenectomy is performed to assess patient prognosis and to prevent metastasizing. Recently, it was questioned whether lymph node metastases were capable of metastasizing and therefore, if lymphadenectomy was still adequate. We evaluated whether the nodal status impacts on the occurrence of distant metastases by analyzing a highly selected cohort of colon cancer patients. Methods 1,395 patients underwent surgery exclusively for colon cancer at the University of Lübeck between 01/1993 and 12/2008. The following exclusion criteria were applied: synchronous metastasis, R1-resection, prior/synchronous second carcinoma, age < 50 years, positive family history, inflammatory bowel disease, FAP, HNPCC, and follow-up < 5 years. The remaining 421 patients were divided into groups with (TM+, n = 75) or without (TM-, n = 346) the occurrence of metastasis throughout a 5-year follow-up. Results Five-year survival rates for TM + and TM- were 21% and 73%, respectively (p < 0.0001). Survival rates differed significantly for N0 vs. N2, grading 2 vs. 3, UICC-I vs. -II and UICC-I vs. -III (p < 0.05). Regression analysis revealed higher age upon diagnosis, increasing N- and increasing T-category to significantly impact on recurrence free survival while increasing N-and T-category were significant parameters for the risk to develop metastases within 5-years after surgery (HR 1.97 and 1.78; p < 0.0001). Conclusions Besides a higher T-category, a positive N-stage independently implies a higher probability to develop distant metastases and correlates with poor survival. Our data thus show a prognostic relevance of lymphadenectomy which should therefore be retained until conclusive studies suggest the unimportance of lmyphadenectomy.

Background: Historical data indicate that surgical resection may benefit select patients with metastatic gastric and gastroesophageal junction cancer. However, randomized clinical trials are lacking. The current RENAISSANCE trial addresses the potential benefits of surgical intervention in gastric and gastroesophageal junction cancer with limited metastases.Methods: This is a prospective, multicenter, randomized, investigator-initiated phase III trial. Previously untreated patients with limited metastatic stage (retroperitoneal lymph node metastases only or a maximum of one incurable organ site that is potentially resectable or locally controllable with or without retroperitoneal lymph nodes) receive 4 cycles of FLOT chemotherapy alone or with trastuzumab if Her2+. Patients without disease progression after 4 cycles are randomized 1:1 to receive additional chemotherapy cycles or surgical resection of primary and metastases followed by subsequent chemotherapy. 271 patients are to be allocated to the trial, of which at least 176 patients will proceed to randomization. The primary endpoint is overall survival; main secondary endpoints are quality of life assessed by EORTC-QLQ-C30 questionnaire, progression free survival and surgical morbidity and mortality. Recruitment has already started; currently (Feb 2017) 22 patients have been enrolled.Discussion: If the RENAISSANCE concept proves to be effective, this could potentially lead to a new standard of therapy. On the contrary, if the outcome is negative, patients with gastric or GEJ cancer and metastases will no longer be considered candidates for surgical intervention.Trial Registration: The article reports of a health care intervention on human participants and is registered on October 12, 2015 under ClinicalTrials.gov Identifier: NCT02578368 ; EudraCT: 2014-002665-30. [ABSTRACT FROM AUTHOR]

In the present work, we focus on long-term and permanent measurements of approximately two years on a 192 kWel Gas Otto CHP (combined heat and power) unit at a full-scale research biogas plant. In detail the influence of 600 h and 1800 h maintenance intervals on electrical efficiency consumption and exhaust gas emissions such as NOx and CO have been studied under real life conditions. Lubricating oil quality analyses throughout the CHP operation time are presented to show the destructive changes in property and its influence on condition based maintenance. The results confirm the well-known fact that after readjustment of the air-fuel ratio after 1800 h maintenance the emission values for NOx decline while CO increases. The emission-optimized operation mode leads to lower engine efficiency. The maintenance tasks carried out at 600 h intervals lead to lower NOx emissions in nine cases while in 14 cases the emissions remained unchanged. The permanent measurements proved their legitimacy showing various emission deviations from the limiting values prior and post maintenance. The results show that by monitoring the lubricating oil quality, the oil change intervals can be maximized while ensuring that engine performance is not endangered, and a longer engine lifespan can be expected. The oil analyses allow the operator to reduce maintenance expenditures while minimizing wear. [ABSTRACT FROM AUTHOR]

This work thoroughly evaluates the electric power consumption of a full scale, 3 × 923 m³ complete stirred tank reactor (CSTR) research biogas plant with a production capacity of 186 kW of electric power. The plant was fed with a mixture of livestock manure and renewable energy crops and was operated under mesophilic conditions. This paper will provide an insight into precise electric energy consumption measurements of a full scale biogas plant over a period of two years. The results showed that a percentage of 8.5% (in 2010) and 8.7% (in 2011) of the produced electric energy was consumed by the combined heat and power unit (CHP), which was required to operate the biogas plant. The consumer unit agitators with 4.3% (in 2010) and 4.0% (in 2011) and CHP unit with 2.5% (in 2010 and 2011) accounted for the highest electrical power demand, in relation to the electric energy produced by the CHP unit. Calculations show that 51% (in 2010) and 46% (in 2011) of the total electric energy demand was due to the agitators. The results finally showed the need for permanent measurements to identify and quantify the electric energy saving potentials of full scale biogas plants. [ABSTRACT FROM AUTHOR]

Optimal nutrient supply in the digester is essential for efficient biogas production. The aim of this study was to analyze the effects of various micro- and macronutrients on the process stability by a field test. The digestates of 25 biogas plants across the federal state of Baden- Württemberg, Germany, were investigated. Collected data including trace elements, macronutrients, and volatile fatty acids ( VFA) concentrations, as well as the organic loading rate and hydraulic retention time were subjected to statistical analysis. High variations in the concentrations within the different biogas plants were observed. Statistically significant effects of substrate constituents and process parameters on the stability of the anaerobic digestion process were found. Several micro- and macronutrients and the relationships between these elements, as well as the process parameters propionic acid, acetic acid, and acetic acid equivalent were tested. Ni, Mo, and S had a consistent statistically significant effect, while the organic loading rate and Se only showed an effect limited to the acetic acid concentration and the acetic acid equivalent. No statistically significant effect could be shown for Fe, Co, and Na. Most of the significant interactions between the tested elements contained Ni, Fe, and Co. This shows that a balanced relation between the concentrations of these elements is of greater importance than the presence of individual elements for a digester to be able to operate at high organic loading rates and maintain low VFA concentrations. [ABSTRACT FROM AUTHOR]

Batch anaerobic dry digestion promises further application in agriculture and for treatment of municipal solid waste, especially with smaller substrate throughputs. As in other anaerobic systems, bacteriological activity is inhibited by lack of moisture and in batch dry digestion liquid is sprinkled over the substrate to encourage biomass degradation and biogas production throughout the process. Laboratory-scale experiments were carried out to investigate individual methane generation from the recirculated liquid phase and from the stacked solid material. Results clearly indicate that methane formation within the recirculated liquid significantly adds to the total methane production of the process. Up to 21% of the total methane generation originated from the recirculated liquid. This suggests that methane generation from the liquid phase is not to be neglected and needs to be recuperated. The process water tank should be equipped with gas collection facilities. Experimental results further indicate that higher ratios of easily hydrolysable substrates increase the proportion of methane from the liquid phase while slowly hydrolysable material encourages biogas generation in the decomposing biomass bed itself. While the amount of easily hydrolysable biomass in the system and the ratio of methane produced in the liquid phase could be positively correlated, no correlation was possible between the volume of liquid in the process water tank and the methane proportion originating from the liquid phase. [ABSTRACT FROM AUTHOR]

This article discusses the concentrations of particulate matter in dust emission from swine facilities in Germany and Italy. The authors measured climate and airborne particulate matter using scatter light photometry and ventilation as well as animal data such as feeding times, activity and weight. A dynamic transfer function simulation model was used to model dust concentrations and emissions. They found that the measured dust peaks did not always correspond to the measured activity levels. They recommended improved continuous and accurate measurements of input variables and optimization of measuring days.

The enhancement of the degradation rate of energy crops, agricultural residues and manure by different lab scale pretreatment pathways is shown in previous studies. In general, the pretreatments resulted in higher degradation efficiencies and an increase in methane yield for lignocellulosic and fibrous biomass. The major drawback of most of the different pretreatment methods is that either they are not feasible for application in practice or the high energy demand makes them economically inefficient. The aim of this study was to evaluate the effects of a full-scale mechanical pretreatment with a cross-flow grinder on commonly used energy crops (maize silage, grass silage and rye grain silage) and horse manure. Furthermore, the optimal treatment intensity for the highest energy output was estimated. A grinding time of 15 s led to a significant increase in methane yield for horse manure (+ 9.2%) and a mixture of energy crops and horse manure (+ 9.7%). However, only lower treatment intensities proved to have a positive energy balance. An increase in treatment intensity resulted in a further reduction of particle size but showed no effects on the degradation efficiency. Hence, it can be concluded that the utilization of the mechanical treatment enables the digestion of lignocellulosic and fiber-rich substrates like residuals and organic wastes and therefore increases the environmental sustainability of energy production by anaerobic digestion. [ABSTRACT FROM AUTHOR]

Abstract: Experiments on methanogenesis from horse dung were conducted in laboratory-scale batch reactors in order to determine the substrate performance in a solid-phase digestion process, more specifically in terms of potential energy recovery and suitable process technology. Dung from a horse stable with straw bedding was used. The temperature was kept in the mesophilic range. In the percolation process (with process water sprinkled over the stacked biomass) a proportion of 10–20% of solid inoculum (pre-digested horse dung) was found to be suitable. Comparative experiments with both percolation and flooding revealed a higher biogas production per volume for the flooded process, as no addition of solid inoculum was necessary. Methane yield from fresh material was similar in both processes: around 170 LN CH4 per kg VS added was obtained in six-week cycles with untreated material under optimized conditions. Methane production was increased after chopping the substrate. Pre-aeration resulted in decreased methane production. [Copyright &y& Elsevier]

Evaporation of water to the ambient air is generally a cost-effective solution to alleviate heat stress but is also critically discussed due to its increasing effect on indoor humidity. The objectives of this study were to investigate the impact on indoor temperature, humidity, and ventilation rate using a high-pressure fogging system inside a mechanically ventilated research facility for fattening pigs. Data were sampled quasi-continuously throughout four fattening periods, including information on water consumption and energy use of the fogging system, as well as on the average weight gain of the pigs. It was found that for the pigs, the positive effects of the reduction of sensible indoor temperature exceeded the negative effects of the increased humidity, mirrored e.g. by a reduction of the temperature–humidity index (alert situations were reduced from 15.5% to 0.8%) and an increased weight gain of the animals during hot summer conditions. Main effects were achieved on days with mean daily outside temperatures above 14°C, during which water consumption of the fogging system averaged 4.9ld−1 pig−1. The evaporation characteristics, such as the evaporative fraction as well as the time constant for reaching a steady state, were evaluated using a transfer-function model. Both were influenced largely by temperature and saturation deficit. While the evaporative fraction was 100% during steady state and 63% of steady state was reached within 65s during warm and dry ambient conditions (28°C; 53% relative humidity RH), the evaporative fraction dropped to 89% and 65% for moderate (21°C; 69% RH) and cold/humid (13°C; 83% RH) indoor conditions, respectively, and the time to reach steady state was nearly doubled for the latter. The information about such evaporation characteristics is crucial for an accurate control of fogging and ventilation. [Copyright &y& Elsevier]

Electronic animal identification is an important technology in modern animal husbandry providing great benefits. Low-frequency applications are state-of-the-art within the radio frequency identification of animals. Quasi-simultaneous detection of several animals and reading of the transponders over longer distances is impossible with low-frequency systems. Ultra-high-frequency (UHF) applications are suitable for this purpose. However, UHF systems have disadvantages through their susceptibility to metallic surfaces and liquids. Thus, the reflection and absorption of electromagnetic radiation in the animals' environment is often problematic. Consequently, an adjustment of the transponder ear tags regarding mechanical stability and functionality close to water (ear tissue) is necessary. In this project, targeted adjustments and a further development of UHF transponder ear tags concerning the resonance frequency were made. Three trials with cattle and two trials with pigs were performed in this study. Cattle were driven through a reader gate for ten rounds and six different types of transponder ear tags designed in-house were tested. The influence of the environment (indoor vs. outdoor), reader orientation at the gate (sideways vs. above) and output power of the readers (1.0 vs. 0.5 W) were tested in two experiments. The average number of readings per round and the reading rates of the transponder ear tag types were taken as target variables. In the trials with pigs, three transponder ear tag types were compared. The animals were driven through the gate for five rounds per repetition, but neither the reader output power nor the reader orientation were varied. The pig experiments were performed indoors. The results of the cattle experiments showed that the average number of readings per round and the reading rates were significantly higher indoors compared to outdoors. The reader output power of 1.0 W achieved significantly better results compared to 0.5 W. The same applied to the reader orientation ‘above’ compared to ‘sideways’. It could also be shown that an improvement of the transponder and, thus, an adjustment to the animal's ear could be achieved during transponder ear tag type development. A maximum reading rate of 100% was reached with the cattle transponder types finally developed (B3-4, B4-4 and B5). In addition, an average reading rate of 100% was achieved for one pig transponder ear tag type (C2). However, these experiments have to be treated with caution due to a very low sample size. [ABSTRACT FROM AUTHOR]

During recent years the renewable energy production with agricultural biomass became more and more important. The increased use of agricultural products instead for nutrition aroused a debate. Therefore, the utilization of agricultural byproducts and residuals for anaerobic digestion is the essential step for the future sustainable energy production. One available substrate would be horse manure, but literature is still lacking information about gas potential and digestibility of horse manure in biogas plants. This work aims at investigating the suitability of horse manure with different bedding materials and to produce standard values for different horse manure samples. Additionally the methane yields of the components of the horse manure were analyzed. The results of the batch digestion test showed the highest specific methane yields for straw pellets with 0.247 Nm³ CH4 kg-1 VS. Slightly lower are the values for the straw samples in range of 0.183 to 0.237 Nm³ CH4 kg-1 VS. The digestion of alternate bedding materials like flax and woody materials leads to specific methane values beneath 0.100 Nm³ CH4 kg-1 VS. Based on these results these materials should be avoided for anaerobic digestion. The straw based horse manure produced 0.191 ± 0.02 Nm³ CH4 kg-1 VS in the batch assay. The storage of the manure resulted in significant lower methane yields. Hence, the anaerobic digestion of the straw based horse manure is an efficient conversion pathway and can help to avoid the utilization of acreage for energy production instead of the production of food. [ABSTRACT FROM AUTHOR]

A recently developed control strategy for the anaerobic digestion process requires secure knowledge about the state of the process. The near infrared reflection spectroscopy (NIRS), provides the possibility to determine process parameters of the anaerobic digestion process online and directly at the digester. To investigate if the NIRS measurements can successfully be used for the characterization of the state of the process within the control strategy the control was operated on two experimental digesters. The NIR spectra were recorded during the experiments. The values of the process parameters (mainly concentrations of organic acids) obtained by NIRS differ from the values of the chemical analyses during the experiment. Nevertheless the state of the process is categorized equally on the basis of both measurement methods. It can consequently be stated that NIRS is expected to meet the requirements of the control strategy. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H2S) is a critical component of biogas formed under anaerobic conditions by sulfur and sulfate reducing bacteria from animal manure and renewable energy crops. H2S causes high corrosion in equipment, has a negative environmental impact, inhibits the biogas formation process and is furthermore odorous and toxic. Although several methods for internal and external desulfunzation found their way into practice and had been explored at laboratory scale, no data were available on the performance of such methods in full scale practice, especially for an external fixed-bed trickling bioreactor (FBTB). The effects of temperature, pH and air ratio on H2S removal efficiency (RE) were studied. The study was conducted at a research biogas plant with a given output of 96 m³ biogas per hour, and an H2S concentration ranging between 500 ppm and 600 ppm (1 ppm=1 c³/³) on average. The FBTB colunm has been designed to hold a packing volume of 2.21 m³ at a gas retention time of 84 seconds being loaded at an average of 32.88 g H2S/(m³-h). The highest H2S RE of 98% was found at temperatures between 30 °C and 40°C. A major decline in RE to 21 %-45% was observed at temperatures from 5 °C to 25 °C. The results clearly showed a temperature optimum range for sulfate reducing bacteria. The results reveal that RE is little affected by different pH values and air ratios. During the experimental period, the practical suitability of the FBTB system could be proved while avoiding the disadvantages of internal biological desulfurization methods. Keywords: external biological desulfurization, fixed-bed trickling bioreactor (FBTB), H2S removal efficiency (RE), hydrogen sulfide, biogas, full scale biogas research plant [ABSTRACT FROM AUTHOR]

Background: Radiofrequency ablation (RFA) and electrochemical treatment (ECT) are two methods of local liver tumor ablation. A reproducible perfusion model allowed us to compare these methods when applied in proximity to vascular structures. Material and Methods: In a porcine liver perfusion model, we used RFA (group A) and ECT (group B) to perform ablations under ultrasound guidance within 10 mm of a vessel and examined the induced necrosis macroscopically and histologically. Results: We created 83 lesions (RFA: 59, ECT: 24) in 27 livers. In group A (mean liver weight: 2046 g), perfusion was macroscopically found to limit necrosis in 52.5% of the procedures. Histology demonstrated the destruction of only 30.4% of the vessel walls within the ablation areas. In group B (mean liver weight: 1885 g), we detected reproducible and sharply demarcated ablation areas both macroscopically and histologically. Necrosis was unaffected by nearby vessels. No viable cells were found perivascularly. Histology showed destruction of the vascular endothelium without any discontinuities. We measured pH values of 0.9 (range: 0.6–1.8) at the anode and 12.2 (range: 11.4–12.6) at the cathode. Treatment time was 100 min when a charge of 300 coulombs was delivered. Conclusions: Electrochemical treatment is a method of ablation that creates reproducible and predictable volumes of necrosis. It produces sharply demarcated areas of complete necrosis also in perivascular sites. ECT, however, requires much longer treatment times than RFA. In our model, the effects of RFA were considerably limited by perfusion, which caused incomplete areas of necrosis in proximity to vessels. [ABSTRACT FROM AUTHOR]

Objective: Pain is the main symptom of chronic pancreatitis. However, in addition to an improvement in pain symptoms, an increase in the quality of life also influences therapeutic success. The present paper evaluates the influence of surgery on chronic pancreatitis, and the early and late postoperative quality of life., Patients: From March 2000 until April 2005, 51 patients underwent surgical treatment for chronic pancreatitis at our institution., Intervention: Thirty-nine (76.5%) patients were operated on according to the Frey procedure and, in 12 (23.5%) patients, a Whipple procedure was performed., Study Design: Patient data were documented throughout the duration of the hospital stay. Postoperative follow-up data were recorded retrospectively., Main Outcome Measures: Postoperative follow-up with postoperative pain scores and quality of life were carried out using a standardized questionnaire., Results: During a median follow-up period of 50 months, an improvement in pain scores was observed in 92.3% of the patients in the Frey group and in 66.7% in the Whipple group. The indices for global quality of life and for physical and emotional status increased in both surgical groups., Conclusion: For patients with chronic pancreatitis, the decisive factor is the quality of life, particularly concerning pain and metabolic changes. The Frey procedure seems to offer advantages with respect to long-term freedom of pain and low risk of surgery-induced pancreatic insufficiency.

In this pilot study, we tested whether a soft mat (foam covered with a heat-sealed thermoplastic) reduces alterations and injuries at the skin and the leg joints.The soft mat in the lying area of partly slatted pens was compared to a lying area consisting of either bare or slightly littered (100 g straw per pig and day) concrete flooring. In this study we focused on skin lesions on the legs of finishing pigs as indicators of impaired welfare. Pigs were kept in 19 groups of 8-10 individuals and were examined for skin lesions around the carpal and tarsal joints either at a weight of <35 kg, or at close to 100 kg. The likelihood of hairless patches and wounds at the tarsal joints was significantly lower in pens with the soft lying mat than in pens with a bare concrete floor. Pens with a littered concrete floor did not differ compared to pens with a bare concrete floor. The soft lying mat thus improved floor quality in the lying area in terms of preventing skin lesions compared to bare and slightly littered concrete flooring. Such soft lying mats have thus the potential to improve lying comfort and welfare of finishing pigs.

Influences on dust emissions from livestock operations are number, weight, and kind of animals and characteristics of the housing system. Differences between facilities cannot be explained solely by mechanistic input variables. The objective of this study was to characterize the main input variables for modeling emissions of particulate matter with a mass median diameter < or = 10 microm (PM10) from swine facilities using a data-based model. Investigations were performed in mechanically ventilated facilities for weaning, growing-finishing, and sows in Italy and Germany. The measurements included inside and outside concentration of airborne PM10 particles (scatter light photometry), ventilation rate (calibrated measuring fans), indoor air climate at a measuring frequency of 60 s, feeding times, and animal-related data such as weight and animal activity. Dust concentration and emission were simulated using a dynamic transfer function. The results indicated that the average PM10 emission rate was influenced considerably by housing system. The simulation of the PM10 emission rate resulted in a mean percentage error per data set of 21 to 39%, whereas the average simulated and measured emission rate per data set differed by about 4 to 19%. High prediction errors occurred especially during situations in which the absolute level and spatial location of the measured activity peaks did not correspond with the measured dust peaks. Further recommendations of the study were to improve continuous and accurate measurements of input variables, such as the activity level in animal houses, and to optimize the amount of measuring days in relation to the model accuracy.