Temporal offset between precipitation and water uptake of Mediterranean pine trees varies with elevation and season.

For climate models that use paleo-environment data to predict future climate change, tree-ring isotope variations are one important archive for the reconstruction of paleo-hydrological conditions. Due to the rather complicated pathway of water, starting from precipitation until its uptake by trees and the final incorporation of its components into tree-ring cellulose, a closer inspection of seasonal variations of tree water uptake is important. In this study, branch and needle samples of two pine species (Pinus pinaster and Pinus nigra subsp. laricio) and several water compartments (precipitation, creek, soil) were sampled over a two-year period and analyzed for the temporal variations of their oxygen and hydrogen stable isotope ratios (δ18O and δ2H) at five sites over an elevation gradient from sea level to around 1600 m a.s.l. on the Mediterranean island of Corsica (France). A new model was established to disentangle temporal relationships of source water uptake of trees. It uses a calculation method that incorporates the two processes mostly expected to affect source water composition: mixing of waters and evaporation. The model results showed that the temporal offset from precipitation to water uptake is not constant and varies with elevation and season. Overall, seasonal source water origin was shown to be dominated by precipitation from autumn and spring. While autumn precipitation was a more important water source for trees growing at mid- (~800-1000 m a.s.l) and high-elevation (~1600 m a.s.l.) sites, trees at coastal sites mostly took up water from late winter and spring. These findings show that predicted decreases in precipitation amounts during the wet season in the Mediterranean can have strong impacts on water availability for pine trees, especially at higher elevations.

Climate variability rather than overstocking causes recent large scale cover changes of Tibetan pastures.

The Tibetan Plateau (TP) is a globally important "water tower" that provides water for nearly 40% of the world's population. This supply function is claimed to be threatened by pasture degradation on the TP and the associated loss of water regulation functions. However, neither potential large scale degradation changes nor their drivers are known. Here, we analyse trends in a high-resolution dataset of grassland cover to determine the interactions among vegetation dynamics, climate change and human impacts on the TP. The results reveal that vegetation changes have regionally different triggers: While the vegetation cover has increased since the year 2000 in the north-eastern part of the TP due to an increase in precipitation, it has declined in the central and western parts of the TP due to rising air temperature and declining precipitation. Increasing livestock numbers as a result of land use changes exacerbated the negative trends but were not their exclusive driver. Thus, we conclude that climate variability instead of overgrazing has been the primary cause for large scale vegetation cover changes on the TP since the new millennium. Since areas of positive and negative changes are almost equal in extent, pasture degradation is not generally proceeding.

Expectant management of PPROM and major complications before planned delivery: a retrospective cohort study.

Women with pre-term pre-labour rupture of membranes (PPROM) 22-33 weeks' gestation were included in a retrospective cohort study with a structured audit to identify risk factors of major complications following PPROM and to assess whether these complications are predictable. Of the 234 women analysed, 106 (45%) delivered within three days. Eighty-four women (36%) had at least one major complication and 45% of these complications occurred within three days. The complication rate was 64% in early PPROM before 28 weeks' gestation and 11% in late PPROM at 28 weeks' gestation or later. Nulliparous women had an increased risk of major complications (adjusted hazards ratio: 3.07 (95% confidence interval: 1.28-7.37)). The complication rates were highest in early PPROM and during the first three days after PPROM. Multiparous women with late PPROM, who do not deliver within the first three days, have the lowest risk of major complications and are suitable for home care.

The Peptic Ulcer Perforation (PULP) score: a predictor of mortality following peptic ulcer perforation. A cohort study.

BACKGROUND: Accurate and early identification of high-risk surgical patients with perforated peptic ulcer (PPU) is important for triage and risk stratification. The objective of the present study was to develop a new and improved clinical rule to predict mortality in patients following surgical treatment for PPU. DESIGN: nationwide cohort study based on prospectively collected data. SETTING: thirty-five hospitals in Denmark. PATIENTS: a total of 2668 patients surgically treated for gastric or duodenal PPU between 1 February 2003 and 31 August 2009. OUTCOME MEASURE: 30-day mortality. RESULTS: We derived a new clinical prediction rule for 30-day mortality and evaluated and compared its prognostic performance with the American Society of Anaesthesiologists (ASA) and Boey scores. A total of 708 patients (27%) died within 30 days of surgery. The Peptic Ulcer Perforation (PULP) score - comprised eight variables with an adjusted odds ratio of more than 1.28: 1) age > 65 years, 2) active malignant disease or AIDS, 3) liver cirrhosis, 4) steroid use, 5) time from perforation to admission > 24 h, 6) pre-operative shock, 7) serum creatinine > 130 µM, and 8) the four levels of the ASA score (from 2 to 5). The score predicted mortality well (area under receiver operating characteristics curve (AUC) 0.83). It performed considerably better than the Boey score (AUC 0.70) and better than the ASA score alone (AUC 0.78). CONCLUSION: The PULP score accurately predicts 30-day mortality in patients operated for PPU and can assist in risk stratification and triage.

Note: simple means for selective removal of the 365 nm line from the Hg spectrum using Dy.

The emission spectrum of mercury has a notable line at about 365 nm under both low and medium-high pressure conditions. A simple filter based on a solution of dysprosium ions, Dy(3+), is shown to be very useful for applications of Hg-light sources where this line is unwanted. The presented filter is cheap, robust, and stable towards degradation or bleaching - even under intense irradiation. The absorption spectrum for the Dy-filter is presented along with emission spectra from both low-pressure and high-pressure Hg-lamps to illustrate the utility of the technique under best-case and worst-case conditions. Attenuation of the 365 nm spectral line is almost total for the low-pressure source whereas for the high-pressure source the attenuation is about a factor of three.

Reduced cannabinoid receptor 1 protein in subcutaneous adipose tissue of obese.

BACKGROUND: Cannabinoid 1 receptors are identified in various tissues involved in the internal metabolism including adipose tissue and the endocannabinoid system is claimed to be overactive in the obese state. To study the potential involvement of cannabinoid receptor 1 in the endocannabinoid system over-activity in adipose tissue in the obese state, we investigated the cannabinoid receptor 1 levels in adipose tissue from different fat depots in lean and obese humans. MATERIALS AND METHODS: The adipose tissue samples were analysed by Western blot and by RT-PCR. RESULTS: Both the gene expression and the protein of cannabinoid receptor 1 were lower in subcutaneous abdominal adipose tissue from obese subjects as compared with lean subjects (P < 0.01 and P = 0.058). Moreover, in lean subjects, the level of cannabinoid receptor 1 was significantly higher in subcutaneous adipose tissue compared with visceral adipose tissue (P < 0.05) for both gene expression and protein. The level of cannabinoid receptor 1 was similar between the two depots in obese subjects. The expression of cannabinoid receptor 1 was higher in subcutaneous gluteal adipose tissue as compared with subcutaneous abdominal adipose tissue (P < 0.05). CONCLUSION: We found in lean subjects, a robust lower level of cannabinoid receptor 1 in visceral adipose tissue compared with subcutaneous adipose tissue (both RNA and protein levels), but similar levels of cannabinoid receptor 1 between the two depots in obese subjects. Our present findings do not indicate that cannabinoid receptor 1 is directly involved in the endocannabinoid system over-activity in adipose tissue in obesity.

Intraductal papillary mucinous tumor of the pancreas (IPMT): follow-up of twelve cases.

INTRODUCTION: Intraductal papillary mucinous tumours (IPMT) were described as a distinct entity in I982. The extent of surgical resection for this disease remains controversial. METHODS: Twelve patients with a diagnosis of IPMT were included in the present retrospective study. RESULTS: Ten out of twelve patients had symptoms suggesting chronic pancreatitis. Two patients were not operated on due to biopsy-verified metastases in the liver. Nine patients were treated with a total pancreatectomy and one with a pancreaticoduodenectomy. In the ten patients operated on for IPMT, histological examination showed eight non-invasive- and two invasive carcinomas. In six cases, multifocal extensive intraductal changes were found, affecting either most of or the whole pancreas. There was no perioperative mortality. Six patients were alive at follow-up without recurrence and four patients were dead, two of them with recurrence. CONCLUSION: IPMTs represent a subgroup of pancreatic neoplasms with a favourable prognosis, and the resection should aim at removing all dysplastic foci. In cases with diffuse dilatation of the main pancreatic duct, widespread tumour involvement of the duct system can be expected and total pancreatectomy should be the operation of choice.

On the analysis of magnetization and Mössbauer data for ferritin.

Experimental data for antiferromagnetic nanoparticles are often analyzed as if the particles were ferromagnetic. However, due to the volume dependence of the magnetization resulting from uncompensated spins, such analysis will yield erroneous results. This is demonstrated as we analyze ac and dc magnetization data as well as Mössbauer spectra obtained for ferritin. The values of the median energy barrier obtained from the different data are in very close agreement when a distribution of volumes and a volume dependence of the magnetization are taken into account. However, when the volume dependence of the magnetization is neglected, erroneous values of the anisotropy energy barrier and the attempt time τ(0) are obtained.

Seasonality of weather and tree phenology in a tropical evergreen mountain rain forest.

Flowering and fruiting as phenological events of 12 tree species in an evergreen tropical mountain rain forest in southern Ecuador were examined over a period of 3-4 years. Leaf shedding of two species was observed for 12 months. Parallel to the phenological recordings, meteorological parameters were monitored in detail and related to the flowering and fruiting activity of the trees. In spite of the perhumid climate of that area, a high degree of intra- and inter-specific synchronisation of phenological traits was apparent. With the exception of one species that flowered more or less continuously, two groups of trees could be observed, one of which flowered during the less humid months (September to October) while the second group started to initiate flowers towards the end of that phase and flowered during the heavy rains (April to July). As reflected by correlation coefficients, the all-time series of meteorological parameters showed a distinct seasonality of 8-12 months, apparently following the quasi-periodic oscillation of precipitation and related cloudiness. As revealed by power spectrum analysis and Markov persistence, rainfall and minimum temperature appear to be the only parameters with a periodicity free of long-term variations. The phenological events of most of the plant species showed a similar periodicity of 8-12 months, which followed the annual oscillation of relatively less and more humid periods and thus was in phase or in counter-phase with the oscillations of the meteorological parameters. Periods of unusual cold or dryness, presumably resulting from underlying longer-term trends or oscillations (such as ENSO), affected the homogeneity of quasi-12-month flowering events, fruit maturation and also the production of germinable seeds. Some species show underlying quasi-2-year-oscillations, for example that synchronise with the development of air temperature; others reveal an underlying decrease or increase in flowering activity over the observation period, influenced for instance by solar irradiance. As Ecuador suffers the highest rate of deforestation in South America, there is an urgent need for indigenous plant material for reforestation. A detailed knowledge of the biology of reproduction in relation to governing external factors (mainly climate) is thus required.

Coagulation, inflammatory, and stress responses in a randomized comparison of open and laparoscopic repair of recurrent inguinal hernia.

BACKGROUND: In previous comparisons of inflammatory and stress responses to open (OR) and laparoscopic (LR) hernia repair, all operations were performed under general anesthesia. Since local anesthesia is widely used for OR, a comparison of this approach with LR seemed relevant. METHODS: Patients with recurrent inguinal hernia were randomized to OR under local anesthesia (n = 30) or LR under general anesthesia (n = 31). The magnitude of the surgical trauma was assessed by measuring markers of coagulation (prothrombin fragment 1 + 2), endothelial activation (von Willebrand factor), inflammation [leukocytes, interleukin-6, -8 and -10, granulocyte macrophage colony-stimulating factor, and C-reactive protein (CRP)], and endocrine stress (cortisol) in blood collected before operation, 4 h postincision, and on postoperative day 2. RESULTS: Leukocyte counts and interleukin-6 and CRP levels increased in both groups, with the CRP increase being significantly greater in the OR group. The other markers did not increase significantly. CONCLUSION: The acute phase response was more pronounced after OR, even when this was done under local anesthesia. Both techniques seemed rather atraumatic.

Prospective nationwide analysis of laparoscopic versus Lichtenstein repair of inguinal hernia.

BACKGROUND: According to a Cochrane review, laparoscopic inguinal hernia repair compares favourably with open mesh repair, but few data exist from surgical practice outside departments with a special interest in hernia surgery. This study compared nationwide reoperation rates after laparoscopic and Lichtenstein repair, adjusting for factors predisposing to recurrence. METHODS: Some 3606 consecutive laparoscopic repairs were compared with 39 537 Lichtenstein repairs that were prospectively recorded in a nationwide registry between 1998 and 2003. Patients were subgrouped according to type of hernia: primary or recurrent and unilateral or bilateral. Overall reoperation rates and 95 per cent confidence intervals were calculated. Long-term reoperation rates were estimated using the Kaplan-Meier method. RESULTS: The overall reoperation rates after laparoscopic and Lichtenstein repair of unilateral primary indirect hernia (0 versus 1.0 per cent), primary direct hernia (1.1 versus 3.1 per cent), unilateral recurrent hernia (4.6 versus 4.8 per cent) and bilateral recurrent hernia (2.6 versus 7.6 per cent) did not differ. However, laparoscopic repair of a bilateral primary hernia was associated with a higher reoperation rate than Lichtenstein repair (4.8 versus 3.0 per cent) (P = 0.017). CONCLUSION: Laparoscopic repair compared favourably with Lichtenstein repair for primary indirect and direct hernias, and unilateral and bilateral recurrent hernias, but was inferior for primary bilateral hernias.

Convalescence after inguinal herniorrhaphy.

BACKGROUND: Convalescence after inguinal herniorrhaphy is usually 3-4 weeks and is an important outcome parameter of hernia surgery. The aim of this study was to describe in detail the consequences of recommending a short convalescence, including the risk of recurrence. METHODS: This was a multicentre prospective questionnaire study in patients given a recommendation for short convalescence (1 day); information was recorded on expected length of convalescence, employment status, physical workload and limiting factors. The reoperation rate in patients included in the study (group 1, n = 1059) was compared with that for comparable patients treated in participating departments but not part of the study group (group 2, n = 1306) and patients in the Danish Hernia Database (group 3, n = 8297). RESULTS: The median time off work was 7 days and the time interval before carrying out the most strenuous leisure activity was 14 days. After 30 days, 6.8 per cent of patients had not resumed employment and 17.0 per cent had not yet resumed strenuous leisure activity. Important reasons for not resuming work and leisure activity were pain (approximately 60 per cent of patients) and wound problems (approximately 20 per cent). The reoperation rate in group 1 at the median observation time was 0.7 per cent, which was no different to that in group 2 (1.6 per cent) (P = 0.186) or group 3 (1.4 per cent) (P = 0.092). CONCLUSION: Reduced convalescence after inguinal herniorrhaphy may be recommended without incurring a risk of higher reoperation rates. Pain and wound problems remain the most important factors for not resuming work or leisure activity as recommended.

Randomized clinical trial of virtual reality simulation for laparoscopic skills training.

BACKGROUND: This study examined the impact of virtual reality (VR) surgical simulation on improvement of psychomotor skills relevant to the performance of laparoscopic cholecystectomy. METHODS: Sixteen surgical trainees performed a laparoscopic cholecystectomy on patients in the operating room (OR). The participants were then randomized to receive VR training (ten repetitions of all six tasks on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR)) or no training. Subsequently, all subjects performed a further laparoscopic cholecystectomy in the OR. Both operative procedures were recorded on videotape, and assessed by two independent and blinded observers using predefined objective criteria. Time to complete the procedure, error score and economy of movement score were assessed during the laparoscopic procedure in the OR. RESULTS: No differences in baseline variables were found between the two groups. Surgeons who received VR training performed laparoscopic cholecystectomy significantly faster than the control group (P=0.021). Furthermore, those who had VR training showed significantly greater improvement in error (P=0.003) and economy of movement (P=0.003) scores. CONCLUSION: Surgeons who received VR simulator training showed significantly greater improvement in performance in the OR than those in the control group. VR surgical simulation is therefore a valid tool for training of laparoscopic psychomotor skills and could be incorporated into surgical training programmes.

Molecular and electronic structure of nitridocyanometalates of chromium(V) and manganese(V): a combined experimental and DFT study.

The six-coordinate complexes [M(N)(CN)5]3- (M = Cr, Mn) have been isolated as salts of robust rhodium amine complexes. [Rh(en)3][Mn(N)(CN)5].H2O (1) and [Rh(tn)3] [Cr(N)(CN)5].2H2O (2) have been characterized by single-crystal X-ray crystallography: 1 crystallizes in the hexagonal space group P6(3) with a = b = 15.810(2) A, c = 13.844(3) A, V = 2996.8(8) A3, and Z = 6; 2 crystallizes in the orthorhombic space group Pbcn with a = 9.723(1) A, b = 14.564(2) A, c = 31.498(4) A, V = 4460.3(8) A3, and Z = 8. In 1, all the anions are oriented with their Mn identical to N directions almost coparallel to the crystallographic 3-fold axis. Polarized single-crystal UV-vis spectroscopy of 1 confirms the validity of the Jørgensen-Ballhausen-Gray d-orbital splitting scheme with the lowest energy transition being dxy-->[dyz,dzx]. Single-crystal EPR spectroscopy of [Cr(N)(CN)5]3- diluted into 1 shows the hyperfine (53Cr) and super-hyperfine (14N) tensors to be quite anisotropic with different major axes. For the hyperfine interaction we observe A Parallel > A Perpendicular, whereas, for the super-hyperfine interaction to the terminal nitrido ligand, the reverse ordering is found: A Perpendicular > A Parallel. The complexes [M(N)(CN)5]3-, trans-[M(N)(CN)4(py)]2-, and [M(N)(CN)4]2- (M = Cr, Mn) were investigated by DFT methods. Good reproduction of the molecular structures, vibrational, and UV-vis spectra was obtained. However, pronounced differences between local density and gradient corrected functionals were observed in the description of the weak bonding to the ligands trans to the nitrido ligand. For the five-coordinate [M(N)(CN)4]2- complexes the LUMO is predicted to be a strongly admixed dz2(M)-pz(M) hybrid.

The Mixed-Valent (µ-Nitrido)dimanganese Complex Anion

Localized valencies are displayed by the Mn(V)-Mn(II) complex ion 1. This is the key finding from X-ray structure analysis, as well as vibrational and EPR spectroscopic invesigations on 1 obtained by the reaction of manganese(II) and [Mn(v)(N)(CN)(5)](3-) salts in aqueous 1 M NaCN solution. Remarkably, the asymmetry is induced by the nitrogen atom bridge.