91 research outputs found
A simulation model to investigate impacts of facilitating quality data within organic fresh food supply chains
Demand for and production of organic fresh food play an increasing role worldwide. As a result, a growing amount of fresh fruits and vegetables has to be transported from predominantly rural production regions to customers mostly located in urban ones. Specific handling and storage conditions need to be respected along the entire supply chain to maintain high quality and product value. To support organic food logistics operations, this work investigates benefits of facilitating real-time product data along delivery and storage processes. By the development of a simulation-based decision support system, sustainable deliveries of organic food from farms to retail stores are investigated. Generic keeping quality models are integrated to observe impacts of varying storage temperatures on food quality and losses over time. Computational experiments study a regional supply chain of organic strawberries in Lower Austria and Vienna. Results indicate that the consideration of shelf life data in supply chain decisions allow one to reduce food losses and further enables shifting surplus inventory to alternative distribution channels
A decision support system to facilitate collaborative supply of food cooperatives
Food cooperatives are gaining popularity due to consumers’ desire to eat healthy and source locally. Mainly run by private citizens, such groups present an interesting additional income source to regional organic farmers. However, small order quantities and substantial logistics efforts challenge operations. To facilitate efficient and sustainable food transports from farms to food cooperatives, this work investigates impacts of collaborative logistics activities through the development of a simulation and optimization-based decision support system. Results of computational experiments considering fresh food transports in Austria highlight potentials of such joint activities. Particularly, if orders are infrequent and quantities small, collaboration results in a substantial reduction of travel distances and reduces the number of required vehicles. Nevertheless, delivered food quality may deteriorate as consolidating shipments results in longer travel durations as well as additional loading and unloading activities
An econometric analysis of the Australian Country Party, 1922-1928
This study identifies the formation, in the years immediately following the First World War, of agrarian
parties in Australia, Canada and New Zealand as a relevant and unresolved problem for comparative
political science research. It constructs a formal theory of agrarian party formation, electoral support and
dissolution, assembles a set of electoral, census and agricultural economic data, specifies a set of statistical
models and estimates these models’ parameters at the Australian (Commonwealth) elections of 1922,
1925 and 1928.
Its results are consistent with its principal hypothesis: the formation and electoral support, in the years
immediately following the First World War, of agrarian parties such as the Australian Country Party was
a consequence of (1) maladjustments in primary producers’ output of agricultural and pastoral commodities
and (2) the collapse, between 1921 and 1922, in the price of many agricultural and pastoral
commodities below the average variable cost of production. The recovery of commodity prices after
1922, together with producers’ adjustment of their average variable cost of commodity production,
weakened the Country Party’s electoral support and thereby engendered its partial dissolution.
This study thus tentatively resolves this problem for research. It also contributes to a greater understanding
of major and non-major political parties, party systems and voter alignments, and the relationship
between economic conditions and electoral behaviour
Serial measurement of neuron specific enolase improves prognostication in cardiac arrest patients treated with hypothermia: A prospective study
<p>Abstract</p> <p>Background</p> <p>Neuron specific enolase (NSE) has repeatedly been evaluated for neurological prognostication in patients after cardiac arrest. However, it is unclear whether current guidelines for NSE cutoff levels also apply to cardiac arrest patients treated with hypothermia. Thus, we investigated the prognostic significance of absolute NSE levels and NSE kinetics in cardiac arrest patients treated with hypothermia.</p> <p>Methods</p> <p>In a prospective study of 35 patients resuscitated from cardiac arrest, NSE was measured daily for four days following admission. Outcome was assessed at ICU discharge using the CPC score. All patients received hypothermia treatment for 24 hours at 33°C with a surface cooling device according to current guidelines.</p> <p>Results</p> <p>The cutoff for absolute NSE levels in patients with unfavourable outcome (CPC 3-5) 72 hours after cardiac arrest was 57 μg/l with an area under the curve (AUC) of 0.82 (sensitivity 47%, specificity 100%). The cutoff level for NSE kinetics in patients with unfavourable outcome (CPC 3-5) was an absolute increase of 7.9 μg/l (AUC 0.78, sensitivity 63%, specificity 100%) and a relative increase of 33.1% (AUC 0.803, sensitivity 67%, specificity 100%) at 48 hours compared to admission.</p> <p>Conclusion</p> <p>In cardiac arrest patients treated with hypothermia, prognostication of unfavourable outcome by NSE kinetics between admission and 48 hours after resuscitation may be superior to prognostication by absolute NSE levels.</p
Dynamic determination of functional liver capacity with the LiMAx test in post‐cardiac arrest patients undergoing targeted temperature management—A prospective trial
Background: Transiently increased transaminases is a common finding after cardiac arrest but little is known about the functional liver capacity (LiMAx) during the post-cardiac arrest syndrome and treatment in the intensive care unit (ICU). The aim of this trial was to evaluate liver function capacity in post-cardiac arrest survivors undergoing targeted temperature management (TTM) in ICU.
Methods: Thirty-two post-cardiac arrest survivors were prospectively included with all patients undergoing TTM at 33 degrees C for 24 hours. Blood samples were collected, and LiMAx testing was performed at days 1, 2, 5, and 10 post-cardiac arrest. LiMAx is a non-invasive, in vivo, dynamic breath test determining cytochrome P450 1A2 (CYP1A2) capacity using intravenous (IV) C-13-methacetin, thus reflecting maximum liver function capacity. Static liver parameters were determined and compared to LiMAx values.
Results: A typical pattern of transiently, mildly increased transaminases was demonstrated without fulfilling the criteria for hypoxic hepatitis (HH). CYP1A2 activity was reduced with slow normalization over 10 days (lowest median 48 hours after cardiac arrest: 228.5 (25-75 percentile 105.2-301.7 mu g/kg/h, P < .05). Parameters reflecting the liver synthetic function were not impaired, as assessed by, in standard laboratory testing.
Conclusion: Liver functional capacity is impaired in patients after cardiac arrest undergoing TTM at 33 degrees C. More data are needed to determine if liver functional capacity may add relevant information, especially in the context of pharmacotherapy, to individualize post-cardiac arrest care
Prognostic value of ‘late’ electroencephalography recordings in patients with cardiopulmonal resuscitation after cardiac arrest
Background: Electroencephalography (EEG) significantly contributes to the neuroprognostication after resuscitation from cardiac arrest. Recent studies suggest that the prognostic value of EEG is highest for continuous recording within the first days after cardiac arrest. Early continuous EEG, however, is not available in all hospitals. In this observational study, we sought to evaluate the predictive value of a 'late' EEG recording 5-14 days after cardiac arrest without sedatives.
Methods: We retrospectively analyzed EEG data in consecutive adult patients treated at the medical intensive care units (ICU) of the Charite-Universitatsmedizin Berlin. Outcome was assessed as cerebral performance category (CPC) at discharge from ICU, with an unfavorable outcome being defined as CPC 4 and 5.
Results: In 187 patients, a 'late' EEG recording was performed. Of these patients, 127 were without continuous administration of sedative agents for at least 24 h before the EEG recording. In this patient group, a continuously suppressed background activity < 10 mu V predicted an unfavorable outcome with a sensitivity of 31% (95% confidence interval (CI) 20-45) and a specificity of 99% (95% CI 91-100). In patients with suppressed background activity and generalized periodic discharges, sensitivity was 15% (95% CI 7-27) and specificity was 100% (95% CI 94-100). GPDs on unsuppressed background activity were associated with a sensitivity of 42% (95% CI 29-46) and a specificity of 92% (95% CI 82-97).
Conclusions: A 'late' EEG performed 5 to 14 days after resuscitation from cardiac arrest can aide in prognosticating functional outcome. A suppressed EEG background activity in this time period indicates poor outcome
The Role of Somatostatin Receptor Scintigraphy on the Diagnosis of Desmoid Tumors
Background. Magnetic resonance imaging is considered as imaging modality of choice in diagnosis of desmoid tumors, though even this technique can lack the ability to distinguish aggressive fibromatosis from other benign or malignant soft tissue tumors. The aim of this study was to investigate if desmoid tumors would show an adequate tracer uptake in somatostatin receptor scintigraphy and moreover to correlate these results with immunohistochemical staining. Patients and Methods. Thirteen patients with desmoid tumors were examined with somatostatin receptor scintigraphy. Additionally, seven of these patients have been tested for the immunohistochemical expression of somatostatin receptor subtype 2A. The results of somatostatin receptor scintigraphy and the results of immunohistochemical staining (somatostatin receptor subtype 2A) were evaluated and correlated. Results. Somatostatin receptor scintigraphy revealed that eight of 13 affected patients (62%) showed an enhanced tracer uptake. On the other hand, the correlation between the results of somatostatin receptor scintigraphy and immunohistochemical investigations was poor (two out of seven cases). Conclusion. The current study demonstrated that desmoid tumors frequently express somatostatin receptor subtype 2, while immunohistochemical investigations did not correlate with these findings. This may likely be due to lack of standardization of this technique and also due to heterogeneous receptor distribution within the tumors
Good neurological outcome despite very low regional cerebral oxygen saturation during resuscitation - a prospective preclinical trial in 29 patients
Background Noninvasive regional cerebral oxygen saturation (rSO2) measurement
using near-infrared spectroscopy (NIRS) might inform on extent and duration of
cerebral hypoxia during cardiopulmonary resuscitation (CPR). This information
may be used to guide resuscitation efforts and may carry relevant early
prognostic information. Methods We prospectively investigated non-traumatic
out-of-hospital cardiac arrest (OHCA) patients on scene. NIRS was started
either during CPR or shortly after (<2 min) return of spontaneous circulation
(ROSC) by emergency medical service (EMS). Outcome was determined at intensive
care unit (ICU) discharge and 6 months after cardiac arrest. Results A total
of 29 OHCA patients were included. In 23 patients NIRS was started during CPR
and in 6 patients immediately after ROSC. 18 (62.1 %) patients did not reach
ROSC. Initial rSO2 during CPR was very low (<50 % in all 23 patients, < 30 %
in 19 of 23 patients) with no significant difference between patients
achieving ROSC and those who did not. Of five patients with ROSC, in whom NIRS
was recorded during CPR, two reached a good six-months outcome (initial rSO2
22 %) and three died during the ICU stay (initial rSO2 15, 16 and 46 %). In
six patients with NIRS started immediately after ROSC (<2 min), rSO2 was
substantially higher (54–85 %) than in patients during CPR (p = 0.006).
Discussion and conclusion Initial frontal brain rSO2 determined by NIRS during
CPR was generally very low and recovered rapidly after ROSC. Very low initial
rSO2 during CPR was compatible with good neurological outcome in our limited
cohort of patients. Further studies are needed to assess in larger cohorts and
more detail the implications of very low initial rSO2 during CPR on scene
Survival, but not the severity of hypoxic–ischemic encephalopathy, is associated with higher mean arterial blood pressure after cardiac arrest: a retrospective cohort study
BackgroundThis study investigates the association between the mean arterial blood pressure (MAP), vasopressor requirement, and severity of hypoxic–ischemic encephalopathy (HIE) after cardiac arrest (CA).MethodsBetween 2008 and 2017, we retrospectively analyzed the MAP 200 h after CA and quantified the vasopressor requirements using the cumulative vasopressor index (CVI). Through a postmortem brain autopsy in non-survivors, the severity of the HIE was histopathologically dichotomized into no/mild and severe HIE. In survivors, we dichotomized the severity of HIE into no/mild cerebral performance category (CPC) 1 and severe HIE (CPC 4). We investigated the regain of consciousness, causes of death, and 5-day survival as hemodynamic confounders.ResultsAmong the 350 non-survivors, 117 had histopathologically severe HIE while 233 had no/mild HIE, without differences observed in the MAP (73.1 vs. 72.0 mmHg, pgroup = 0.639). Compared to the non-survivors, 211 patients with CPC 1 and 57 patients with CPC 4 had higher MAP values that showed significant, but clinically non-relevant, MAP differences (81.2 vs. 82.3 mmHg, pgroup < 0.001). The no/mild HIE non-survivors (n = 54), who regained consciousness before death, had higher MAP values compared to those with no/mild HIE (n = 179), who remained persistently comatose (74.7 vs. 69.3 mmHg, pgroup < 0.001). The no/mild HIE non-survivors, who regained consciousness, required fewer vasopressors (CVI 2.1 vs. 3.6, pgroup < 0.001). Independent of the severity of HIE, the survivors were weaned faster from vasopressors (CVI 1.0).ConclusionsAlthough a higher MAP was associated with survival in CA patients treated with a vasopressor-supported MAP target above 65 mmHg, the severity of HIE was not. Awakening from coma was associated with less vasopressor requirements. Our results provide no evidence for a MAP target above the current guideline recommendations that can decrease the severity of HIE
Deep learning-enabled detection of hypoxic–ischemic encephalopathy after cardiac arrest in CT scans: a comparative study of 2D and 3D approaches
ObjectiveTo establish a deep learning model for the detection of hypoxic–ischemic encephalopathy (HIE) features on CT scans and to compare various networks to determine the best input data format.Methods168 head CT scans of patients after cardiac arrest were retrospectively identified and classified into two categories: 88 (52.4%) with radiological evidence of severe HIE and 80 (47.6%) without signs of HIE. These images were randomly divided into a training and a test set, and five deep learning models based on based on Densely Connected Convolutional Networks (DenseNet121) were trained and validated using different image input formats (2D and 3D images).ResultsAll optimized stacked 2D and 3D networks could detect signs of HIE. The networks based on the data as 2D image data stacks provided the best results (S100: AUC: 94%, ACC: 79%, S50: AUC: 93%, ACC: 79%). We provide visual explainability data for the decision making of our AI model using Gradient-weighted Class Activation Mapping.ConclusionOur proof-of-concept deep learning model can accurately identify signs of HIE on CT images. Comparing different 2D- and 3D-based approaches, most promising results were achieved by 2D image stack models. After further clinical validation, a deep learning model of HIE detection based on CT images could be implemented in clinical routine and thus aid clinicians in characterizing imaging data and predicting outcome
- …