Thermogravimetric substrate analysis for prediction of biogas and methane yields.

Biodegradability of biomass constituents is the reason for the gap between theoretical biogas/methane yield and the maximum yield obtainable in bioconversion. The prediction of biogas/methane yields by applying thermal analysis is a relatively new development in this field. The aim of this study was to develop a bioconversion model based on thermogravimetry. Eleven substrates with a specific biogas yield within the range 104 to 572 mLN per gram of volatile solids were subjected to thermogravimetry and a multi linear regression model was developed to predict biogas and methane yields. The optimum parameters describe biogas and methane yields with a root mean square error of 58.8 and 34.3 mLN per gram of volatile solids respectively. The coefficient of determination for these two datasets was 0.81 and 0.84. A prediction technique based on thermogravimetric analysis appears to be a good alternative to other prediction models.

[Donor liver histology : Joint recommendations of the DGP, DTG and DSO]. / Histologische Diagnostik bei Spenderlebern : Gemeinsame Empfehlungen von DGP, DTG und DSO.

BACKGROUND: The indications, implementation and reporting of liver biopsies for deceased organ donation are not mandatory or regulated. Reliable data on outcome quality and prognostic relevance are therefore not available. Defined standards are thus required to enable meaningful studies and to ensure high data quality of a national transplantation registry. OBJECTIVE: Presentation of a synopsis of available studies and literature-based recommendations. RESULTS AND CONCLUSION: Against the background of an organ shortage and a growing number of older donors, pretransplantation liver histology is of significant relevance to guide clinical decision making. With the joint recommendations of the German Transplantation Society (DTG), the German Society of Pathology (DGP) and the German Organ Transplantation Foundation (DSO) standardized procedures are defined for the first time.

Quantitative elastography of the cervix for predicting labor induction success.

PURPOSE: To evaluate the role of quantitative elastography of the cervix in the prediction of successful labor induction compared to the Bishop score (BS) and ultrasound cervical length (CL). MATERIALS AND METHODS: A prospective pilot study was conducted between July 2010 and June 2011 in patients without preterm membrane rupture undergoing labor induction with vaginal prostaglandins. Before starting induction, the BS, functional CL and cervical tissue strain (TS) were assessed. TS assessment was performed twice using the Tissue Doppler Imaging (TDI) software. Diagnostic accuracy was evaluated for the prediction of the following endpoints: active labor achievement (success vs. failure, time interval < 24 h and < 48 h), vaginal delivery (success vs. failure, time interval < 36 h and < 72 h) and total amount of prostaglandins used for labor induction (< 6 mg and < 12 mg). RESULTS: We analyzed 77 patients with a mean gestational age of 39.7 ± 1.5 weeks of gestation and a mean strain of 0.75 ± 0.17. The TS significantly predicted a failure of labor induction, which occurred in 4 cases, both in mono- and multivariate analysis, independently of the functional cervical length (TS 0.6 ± 0.1). No correlation was found between the TS and other outcomes. The Bishop score and functional cervical length were found to predict only an early response to labor induction (time to active labor < 24 h, time to vaginal delivery < 36 h and PG usage < 6 mg). The diagnostic accuracy was slightly but not significantly improved if both TS and CL were considered. CONCLUSION: Preliminary data show the possible usefulness of quantitative cervical elastography in the prediction of labor induction failure.

Quantitative elastography for cervical stiffness assessment during pregnancy.

AIM: Feasibility and reliability of tissue Doppler imaging-(TDI-) based elastography for cervical quantitative stiffness assessment during all three trimesters of pregnancy were evaluated. MATERIALS AND METHODS: Prospective case-control study including seventy-four patients collected between the 12th and 42nd weeks of gestation. The tissue strain (TS) was measured by two independent operators as natural strain. Intra- and interoperator intraclass correlation coefficient (ICC) agreements were evaluated. RESULTS: TS measurement was always feasible and exhibited a high performance in terms of reliability (intraoperator ICC-agreement=0.93; interoperator ICC agreement=0.89 and 0.93 for a single measurement and for the average of two measurements, resp.). Cervical TS showed also a significant correlation with gestational age, cervical length, and parity. CONCLUSIONS: TS measurement during pregnancy demonstrated high feasibility and reliability. Furthermore, TS significantly correlated with gestational age, cervical length, and parity.

[Family approach--retrospective analysis of 6,617 donation requests]. / Gespräche mit Angehörigen zur Organspende. Retrospektive Analyse von 6,617 Gesprächen.

BACKGROUND: According to surveys the majority of the German population has a positive attitude towards organ donation. However, declarations of will concerning this matter are often missing in case of death. Thus, in nearly all cases consent must be obtained from the family of the deceased. Compared with refusal rates of other countries the refusal rate in Germany (approximately 40%) is rather high. The modification of the German Transplantation Legislation in November 2012 supports the voluntary documentation of everyone's decision with regard to organ donation. METHODS: Based on 6,617 documented donation requests collected between 2009 and 2011, factors were identified, which--besides personal attitude of morality--could influence the decision about donation. RESULTS: The decedent's will is often unknown (67.4%) and the family's decision is based on the suspected will of the patient. This resulted in 4097 (61.9%) consents and 2520 (38.1%) refusals. 4669 (70.6%) of these donation-requests were carried out by the physician in charge and 1948 (29.4%) with the assistance of a coordinator from the German foundation for organ transplantation (DSO). Predictive (p<0.001) for consent were the presence of a specially trained coordinator and the timing of the request for organ donation. CONCLUSION: There is a big discrepancy between the attitude displayed in surveys and the actual consent rate to organ donation. The major challenge is an improved caregiving for the donor family. Donation requests should be made preferably by trained physicians as well as coordinators. Waiting for the finalized certification of brain death may not be appropriate in all cases.

Constraining the astrophysical origin of the p-nuclei through nuclear physics and meteoritic data.

A small number of naturally occurring, proton-rich nuclides (the p-nuclei) cannot be made in the s- and r-processes. Their origin is not well understood. Massive stars can produce p-nuclei through photodisintegration of pre-existing intermediate and heavy nuclei. This so-called γ-process requires high stellar plasma temperatures and occurs mainly in explosive O/Ne burning during a core-collapse supernova. Although the γ-process in massive stars has been successful in producing a large range of p-nuclei, significant deficiencies remain. An increasing number of processes and sites has been studied in recent years in search of viable alternatives replacing or supplementing the massive star models. A large number of unstable nuclei, however, with only theoretically predicted reaction rates are included in the reaction network and thus the nuclear input may also bear considerable uncertainties. The current status of astrophysical models, nuclear input and observational constraints is reviewed. After an overview of currently discussed models, the focus is on the possibility to better constrain those models through different means. Meteoritic data not only provide the actual isotopic abundances of the p-nuclei but can also put constraints on the possible contribution of proton-rich nucleosynthesis. The main part of the review focuses on the nuclear uncertainties involved in the determination of the astrophysical reaction rates required for the extended reaction networks used in nucleosynthesis studies. Experimental approaches are discussed together with their necessary connection to theory, which is especially pronounced for reactions with intermediate and heavy nuclei in explosive nuclear burning, even close to stability.

Detection of potential organ donors: 2-year analysis of deaths at a German university hospital.

OBJECTIVE: In 2006, inhouse coordinators were introduced in all hospitals with intensive care units in Baden-Württemberg to improve organ donation. At our university hospital with a neurosurgery and a transplantation unit, we analyzed whether brain death certification and donation requests were always initiated (if possible). MATERIALS AND METHODS: We retrospectively reviewed all 1312 hospital deaths from 2006-2007 by studying medical records and consulting with physicians. The possibility of organ donation was questioned. RESULTS: Donation was requested among 68/702 deaths due to cerebral complications. A request was impossible in 8 cases. Consent for donation was obtained in 29 cases, and it was realized in 24 cases. In 14 cases of resuscitation from shock or cardiac failure, therapy was not continued because of questionable hemodynamic stability. In 17 cases admitted to peripheral wards and 19 to intensive care units death due to cerebral complications occurred within 48 hours, but medical records were not relevant for exclusion criteria for organ donation. CONCLUSIONS: The detection of donors was not acceptable. In patients without a prognosis after resuscitation, further hemodynamic stabilization was frequently omitted, because organ donation had not been considered. In cases of donation requests the refusal rate was high. We initiated specific training.

[Teleradiology and mammography screening: evaluation of a network with dedicated workstations for reporting]. / Teleradiologie im Mammographie-Screening: Evaluation eines Testnetzes mit dedizierten Befundungsstationen.

PURPOSE: Evaluation of a system that supports a workflow for breast cancer screening by mammography. The time of installation, system reliability and workstation operation were evaluated. MATERIALS AND METHODS: The evaluated system (Image Diagnost, Munich, Germany) contains 2 diagnostic mammography workstations, a centralized server, and 2 Dicom shuttles for exchanging images via a physically existing network structure. Temporary archiving is possible. A mask designed for the needs of mammography screening facilitates assignment of BIRADS categories. The system automatically compares the categories assigned by a first and second reviewer and decides whether a consensus conference should be held. In the event that a conference is needed, the reviews are transmitted to the mammography expert responsible for the screening program and the consensus conference. Images are transferred via ISDN, Germany's National Research and Education Network (in the following DFN) and a central server between 2 sites which are approx. 100 km apart. We evaluated the duration of installation, the reliability of the system, and the usability of the workstation. Since we used curative mammography for evaluating the system, the patient age was noted for comparison. RESULTS: The system was installed in five days. Once installed, the system functioned without any major breakdowns. Mammography units of 2 manufacturers were able to be connected to the system without difficulty. Mammographies of 151 patients were exchanged between the sites and evaluated by 2 radiologists. 57 % of the patients were in the screening age (50-69 years). 9 exams were classified BIRADS 4a, 2 were 4b and 3 were BIRADS 5. The evaluations were technically perfect in 146/151 cases; hanging protocols had to be altered manually in 6 cases; the window/level had to be manually adjusted in 26/151 cases. Magnification was sufficient in all cases. The system exchanges examinations extremely quickly; up to 100 mammography exams may be evaluated in 1 hr. CONCLUSION: The system supports the workflow given by the German Mammography Screening program both locally and in a network.

[Age differences in psychosocial resources and psychological well-being of cancer patients at the start of chemotherapy]. / Altersunterschiede in psychosozialen ressourcen und im befinden von krebspatienten am beginn einer chemotherapie.

It has been suggested that older patients would have fewer resources than younger patients. We assessed psychosocial resources in 361 recently diagnosed cancer patients. Older patients had a stronger internal health-related locus of control but also less hope than younger patients. No age differences were found for self-esteem and perceived social support. In addition, older patients reported lower levels of negative and positive affect. Curative-intended therapy and social support were associated with a more positive affect only in younger patients, whereas hope was only related to older patients' psychological well-being. It is concluded that older cancer patients have similar levels of psychosocial resources compared to younger patients, but that lack of hope is a vulnerability factor for older patients in particular.

Variations in solar luminosity and their effect on the Earth's climate.

Variations in the Sun's total energy output (luminosity) are caused by changing dark (sunspot) and bright structures on the solar disk during the 11-year sunspot cycle. The variations measured from spacecraft since 1978 are too small to have contributed appreciably to accelerated global warming over the past 30 years. In this Review, we show that detailed analysis of these small output variations has greatly advanced our understanding of solar luminosity change, and this new understanding indicates that brightening of the Sun is unlikely to have had a significant influence on global warming since the seventeenth century. Additional climate forcing by changes in the Sun's output of ultraviolet light, and of magnetized plasmas, cannot be ruled out. The suggested mechanisms are, however, too complex to evaluate meaningfully at present.

Neutrino-induced nucleosynthesis of A>64 nuclei: the nu p process.

We present a new nucleosynthesis process that we denote as the nu p process, which occurs in supernovae (and possibly gamma-ray bursts) when strong neutrino fluxes create proton-rich ejecta. In this process, antineutrino absorptions in the proton-rich environment produce neutrons that are immediately captured by neutron-deficient nuclei. This allows for the nucleosynthesis of nuclei with mass numbers A>64, , making this process a possible candidate to explain the origin of the solar abundances of (92,94)Mo and (96,98)Ru. This process also offers a natural explanation for the large abundance of Sr seen in a hyper-metal-poor star.

AhR-agonist-induced transcriptional changes of genes involved in thyroid function in primary porcine thyrocytes.

The Ah receptor (AhR) is a ligand transcription factor mediating toxic effects of chemicals such as dioxins. The 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) and the coplanar polychlorinated biphenyl 126 (PCB 126) are member of the polyhalogenated aromatic hydrocarbons family exerting a variety of toxic effects in a tissue-specific and species-specific manner including thyroid function. In the present study, we aimed to investigate the effects of TCDD (1 and 10 nM) and dioxin-like PCB 126 (306 nM) on the AhR signaling pathway and on the gene expression profiles of key factors involved in thyroid function, including thyroglobulin (TG), thyroid peroxidase (TPO), the sodium iodide symporter (NIS), TSH receptor (TSHR), and cathepsins (Cat B and L), using a primary porcine thyrocyte culture as the experimental model. AhR and ARNT expression was detected both as mRNA and on the protein level. Expression did not vary upon treatment with either TCDD or PCB 126. However, treatment with TCDD and PCB 126 induced an AhR signaling response, as indicated by the expression of the AhR-target gene cytochrome P-450 1A1 (CYP1A1). Both 10 nM TCDD and PCB 126 treatment induced a significant downregulation in the expression of NIS and cathepsin B without affecting any of the other parameters investigated. In conclusion, these data indicate that (a) thyrocytes are targets of TCDD and TCDD-like compounds and (b) there is evidence for two independent most likely AhR-mediated molecular mechanisms, by which these compounds negatively interfere with thyroid function.

Expanded criteria liver donors (ECD): effect of cumulative risks.

UNLABELLED: The use of ECD in liver donors increases the risk of primary non function (PNF). The German Medical Association (2004) defined an ECD, if one of the following conditions existed: high risk of disease transmission, hemodynamic deterioration, donor age > 65years, BMI > 30kg/m2, bilirubine > 51 mmol/l, ASAT or ALAT > 3*reference, sodium > 165 mmol/l, days on ICU > 7, steatosis > 40% or equivalent liver pathologies. The effect of ECD-criteria was assessed. METHODS: Out 422 consecutive donors (1992-2004) with 282 liver grafts were transplanted (LTX) the existing ECD criteria were cumulated per donor (sigmaECD), grouped and compared to the number of grafts used and the one year graft function rate (all grafts/censored for grafts lost due to PNF only). Discrimination was determined by Receiver-Operating-Characteristics (ROC). RESULTS: With increasing sigmaECD the rate of grafts procured declined (sigmaECD = 0: 95% [n = 162], sigmaECD = 1: 62% [n = 146], EECD = 2: 39% [n = 61], sigmaECD = 3: 32% [n = 38], sigmaECD > or = 4: 13% [n = 16], p < 0.0001). Similarly the one year graft function rate diminished (all grafts: sigmaECD = 0: 72%, sigmaECD = 1: 70%, sigmaECD = 2: 75%, sigmaECD = 3: 58%, sigmaECD > or = 4: 0%, p = 0.0801; censored for grafts lost due to PNF: sigmaECD = 0: 99%, sigmaECD = 1: 95%, sigmaECD = 2: 100%, sigmaECD= 3: 67%, sigmaECD > or = 4: 50%, p < 0.0001). The best cut off for prediction of grafts used was a sigmaECD of 0-1 vs. 2-5 (sensitivity 55%, specificity 87%). The one year graft function rate was adversely affected in sigmaECD above 3. All three grafts used for LTX with confirmed severe steatosis at donor operation (n = 3) did not function. CONCLUSION: Grafts from ECD can be used for LTX. Cumulated ECD was associated with an increased risk of PNF requiring retransplantation. Despite this fact not using donors with cumulated ECD will decrease the limited donor pool. Such livers should be ideally allocated regionally to avoid additional ischemic-reperfusion damage.

Intestinal fluid volumes and transit of dosage forms as assessed by magnetic resonance imaging.

AIM: The gastrointestinal transit of sequentially administered capsules was investigated in relation to the availability of fluid along the intestinal lumen by magnetic resonance imaging. METHODS: Water-sensitive magnetic resonance imaging was performed on 12 healthy subjects during fasting and 1 h after a meal. Specifiable non-disintegrating capsules were administered at 7, 4 and 1 h prior to imaging. RESULTS: While food intake reduced the mean fluid volumes in the small intestine (105 +/- 72 mL vs. 54 +/- 41 mL, P < 0.01) it had no significant effect on the mean fluid volumes in the colon (13 +/- 12 mL vs. 18 +/- 26 mL). The mean number of separated fluid pockets increased in both organs after meal (small intestine: 4 vs. 6, P < 0.05; large intestine: 4 vs. 6, P < 0.05). The distribution of capsules between the small and large intestine was strongly influenced by food (colon: 3 vs. 17 capsules, P < 0.01). CONCLUSIONS: The results show that fluid is not homogeneously distributed along the gut, which likely contributes to the individual variability of drug absorption. Furthermore, transport of fluid and solids through the ileocaecal valve is obviously initiated by a meal-induced gastro-ileocaecal reflex.

Influence of weather and climate on subjective symptom intensity in atopic eczema.

The frequent clinical observation that the course of atopic eczema, a skin disease involving a disturbed cutaneous barrier function, is influenced by climate and weather motivated us to analyse these relationships biometrically. In the Swiss high-mountain area of Davos the intensity of itching experienced by patients with atopic eczema was evaluated and compared to 15 single meteorological variables recorded daily during an entire 7-year observation period. By means of univariate analyses and multiple regressions, itch intensity was found to be correlated with some meteorological variables. A clear-cut inverse correlation exists with air temperature (coefficient of correlation: -0.235, P < 0.001), but the effects of water vapour pressure, air pressure and hours of sunshine are less pronounced. The results show that itching in atopic eczema is significantly dependent on meteorological conditions. The data suggest that, in patients with atopic eczema, a certain range of thermo-hygric atmospheric conditions with a balance of heat and water loss on the skin surface is essential for the skin to feel comfortable.

The cysteine-rich domain of human ADAM 12 supports cell adhesion through syndecans and triggers signaling events that lead to beta1 integrin-dependent cell spreading.

The ADAMs (a disintegrin and metalloprotease) family of proteins is involved in a variety of cellular interactions, including cell adhesion and ecto- domain shedding. Here we show that ADAM 12 binds to cell surface syndecans. Three forms of recombinant ADAM 12 were used in these experiments: the cys-teine-rich domain made in Escherichia coli (rADAM 12-cys), the disintegrin-like and cysteine-rich domain made in insect cells (rADAM 12-DC), and full-length human ADAM 12-S tagged with green fluorescent protein made in mammalian cells (rADAM 12-GFP). Mesenchymal cells specifically and in a dose-dependent manner attach to ADAM 12 via members of the syndecan family. After binding to syndecans, mesenchymal cells spread and form focal adhesions and actin stress fibers. Integrin beta1 was responsible for cell spreading because function-blocking monoclonal antibodies completely inhibited cell spreading, and chondroblasts lacking beta1 integrin attached but did not spread. These data suggest that mesenchymal cells use syndecans as the initial receptor for the ADAM 12 cysteine-rich domain-mediated cell adhesion, and then the beta1 integrin to induce cell spreading. Interestingly, carcinoma cells attached but did not spread on ADAM 12. However, spreading could be efficiently induced by the addition of either 1 mM Mn(2+) or the beta1 integrin-activating monoclonal antibody 12G10, suggesting that in these carcinoma cells, the ADAM 12-syndecan complex fails to modulate the function of beta1 integrin.

Characterization of pyrgeometers and the accuracy of atmospheric long-wave radiation measurements.

A detailed characterization is performed to calibrate pyrgeometers, using a newly developed apparatus that contains a blackbody radiation source and the means to vary the temperatures of the pyrgeometer under testing. Calibration measurements cover the parameter space of radiation and instrument temperatures that prevail during field measurements. Dome-temperature measurements, normally provided on pyrgeometers, are inadequate for accurate corrections of the dome emission. A new temperature measurement with three sensors inside the dome at 45° elevation is proposed and has been implemented on several test instruments. This modification and the detailed characterization measurements permit an improved evaluation, based on thorough analysis of the thermal balance of the instrument, leading to a sensitivity factor C and three correction factors, k(1,2,3). Test measurements demonstrate the substantial improvement achieved on the accuracy of atmospheric and terrestrial long-wave radiation measurements, down to ±2Wm(-2).

Earthquakes with non--double-couple mechanisms.

Seismological observations confirm that the pattern of seismic waves from some earthquakes cannot be produced by slip along a planar fault surface. More than one physical mechanism is required to explain the observed varieties of these non-double-couple earthquakes. The simplest explanation is that some earthquakes are complex, with stress released on two or more suitably oriented, nonparallel fault surfaces. However, some shallow earthquakes in volcanic and geothermal areas require other explanations. Current research focuses on whether fault complexity explains most observed non-double-couple earthquakes and to what extent ordinary earthquakes have non-double-couple components.