► The design of a small scale, low cost solar ORC for rural electrification is described. ► A model of the system is developed. ► Several working fluids are compared and the working conditions are ...optimized. ► Expected overall efficiency is about 8%.
Recent interest in small-scale solar thermal combined heat and power (CHP) power systems has coincided with demand growth for distributed electricity supplies in areas poorly served by centralized power stations. One potential technical approach to meeting this demand is the parabolic trough solar thermal collector coupled with an organic Rankine cycle (ORC) heat engine.
The paper describes the design of a solar organic Rankine cycle being installed in Lesotho for rural electrification purpose. The system consists of parabolic though collectors, a storages tank, and a small-scale ORC engine using scroll expanders.
A model of each component is developed taking into account the main physical and mechanical phenomena occurring in the cycle and based on experimental data for the main key components.
The model allows sizing the different components of the cycle and evaluates the performance of the system. Different working fluids are compared, and two different expansion machine configurations are simulated (single and double stage).
Previous studies of surgical timing in patients with hip fracture have yielded conflicting findings on mortality and have not focused on functional outcomes.
To examine the association of timing of ...surgical repair of hip fracture with function and other outcomes.
Prospective cohort study including analyses matching cases of early (< or =24 hours) and late (>24 hours) surgery with propensity scores and excluding patients who might not be candidates for early surgery.
Four hospitals in the New York City metropolitan area.
A total of 1206 patients aged 50 years or older admitted with hip fracture over 29 months, ending December 1999.
Function (using the Functional Independence Measure), survival, pain, and length of stay (LOS).
Of the patients treated with surgery (n = 1178), 33.8% had surgery within 24 hours. Earlier surgery was not associated with improved mortality (hazard ratio, 0.75; 95% confidence interval CI, 0.52-1.08) or improved locomotion (difference of -0.04 points; 95% CI, -0.49 to 0.39). Earlier surgery was associated with fewer days of severe and very severe pain (difference of -0.22 days; 95% CI, -0.41 to -0.03) and shorter LOS by 1.94 days (P<.001), but postoperative pain and LOS after surgery did not differ. Analyses with propensity scores yielded similar results. When the cohort included only patients who were medically stable at admission and therefore eligible for early surgery, the results were unchanged except that early surgery was associated with fewer major complications (odds ratio, 0.26; 95% CI, 0.07-0.95).
Early surgery was not associated with improved function or mortality, but it was associated with reduced pain and LOS and probably major complications among patients medically stable at admission. Additional research is needed on whether functional outcomes may be improved. In the meantime, patients with hip fracture who are medically stable should receive early surgery when possible.
Hip fracture is a common clinical problem that leads to considerable mortality and disability. A need exists for a practical means to monitor and improve outcomes, including function, for patients ...with hip fracture.
To identify and compare the importance of significant prefracture predictors of functional status and mortality at 6 months for patients hospitalized with hip fracture and to compare risk-adjusted outcomes for hospitals providing initial care.
Prospective study with data obtained from medical records and through structured interviews with patients and proxies.
A total of 571 adults aged 50 years or older with hip fracture who were admitted to 4 New York, NY, metropolitan hospitals between August 1997 and August 1998.
In-hospital and 6-month mortality; locomotion at 6 months; and adverse outcomes at 6 months, defined as death or needing assistance to ambulate, compared by hospital, adjusting for patient risk factors.
The in-hospital mortality rate was 1.6%. At 6 months, the mortality rate was 13.5%, and another 12.8% needed total assistance to ambulate. Laboratory values were strong predictors of mortality but were not significantly associated with locomotion. Age and prefracture residence at a nursing home were significant predictors of locomotion (P =.02 for both) but were not significantly associated with mortality. Adjustment for baseline characteristics either substantially augmented or diminished interhospital differences in outcomes. Two hospitals had 1 outcome (functional status or mortality) that was significantly worse than the overall mean while the other outcome was nonsignificantly better than average.
Mortality and functional status ideally should be considered both together and individually to distinguish effects limited to one or the other outcome. Hospital performance for these 2 measures may differ substantially after adjustment, probably because different processes of care are important to each outcome.
Summary
Background
Within a large prospective study, the Global Asthma and Allergy European Network (GA2LEN) has collected skin prick test (SPT) data throughout Europe to make recommendations for SPT ...in clinical settings.
Objective
To improve clinical interpretation of SPT results for inhalant allergens by providing quantitative decision points.
Methods
The GA2LEN SPT study with 3068 valid data sets was used to investigate the relationship between SPT results and patient‐reported clinical relevance for each of the 18 inhalant allergens as well as SPT wheal size and physician‐diagnosed allergy (rhinitis, asthma, atopic dermatitis, food allergy). The effects of age, gender, and geographical area on SPT results were assessed. For each allergen, the wheal size in mm with an 80% positive predictive value (PPV) for being clinically relevant was calculated.
Results
Depending on the allergen, from 40% (blatella) to 87–89% (grass, mites) of the positive SPT reactions (wheal size ≥ 3 mm) were associated with patient‐reported clinical symptoms when exposed to the respective allergen. The risk of allergic symptoms increased significantly with larger wheal sizes for 17 of the 18 allergens tested. Children with positive SPT reactions had a smaller risk of sensitizations being clinically relevant compared with adults. The 80% PPV varied from 3 to 10 mm depending on the allergen.
Conclusion
These ‘reading keys’ for 18 inhalant allergens can help interpret SPT results with respect to their clinical significance. A SPT form with the standard allergens including mm decision points for each allergen is offered for clinical use.
OBJECTIVES: To quantify the interval between injury and hospitalization in older hip fracture patients, to quantify the time from hospital arrival to surgical repair of hip fracture, and to describe ...factors contributing to extended intervals between injury, hospitalization, and surgical repair of hip fracture.
DESIGN: Prospective cohort study.
SETTING: Four hospitals in the New York City metropolitan area.
PARTICIPANTS: Consecutive patients aged 50 and older admitted with diagnosis of hip fracture to these four hospitals between August 1997 and August 1998.
MEASUREMENTS: Time of injury, time of arrival to the emergency room, and time of surgery were recorded and used to calculate intervals between injury and hospital arrival and between hospital arrival and surgical repair.
RESULTS: Of the 571 patients enrolled, 99 (17%) arrived at the hospital more than 24 hours after injury. After hospital arrival, 17 (3%) patients did not have surgery, 166 (29%) had surgery within 24 hours of arrival, and 388 (68.0%) had surgery more than 24 hours after arrival (median 41 hours, range 25–584). For those patients who had surgery after 24 hours, 163 (29.4%) had surgery 25 to 36 hours after hospital arrival, 102 (18.4%) had surgery 37 to 48 hours after arrival, and 123 (22.2%) had surgery more than 48 hours after arrival. The primary reasons for delaying surgery more than 24 hours after hospital arrival were waiting for routine medical clearance (52%) and unavailability of the operating suite or surgeon (29%). Stabilization of associated medical conditions resulted in the lengthiest periods of delay.
CONCLUSION: A wait time of more than 24 hours from hospitalization to surgical repair of hip fracture in older patients is common. Some of this delay time is patient related and some occurs because of systems factors and may be avoidable. The extent to which surgical timing affects survival and functional recovery needs more detailed examination.
Objectives: To examine the relationship between early physical therapy (PT), later therapy, and mobility 2 and 6 months after hip fracture.
Design: Prospective, multisite observational study.
...Setting: Four hospitals in the New York City area.
Participants: Four hundred forty‐three hospitalized older patients discharged after surgery for hip fracture in 1997–98.
Measurements: Patient demographics, fracture type, comorbidities, dementia, number of new impairments at discharge, amount of PT between day of surgery and postoperative day (POD) 3, amount of therapy between POD4 and 8 weeks later, and prefracture, 2‐, and 6‐month mobility measured using the Functional Independence Measure.
Results: More PT immediately after hip fracture surgery was associated with significantly better locomotion 2 months later. Each additional session from the day of surgery through POD3 was associated with an increase of 0.4 points (P=.032) on the 14‐point locomotion scale, but the positive relationship between early PT and mobility was attenuated by 6 months postfracture. There was no association between later therapy and 2‐ or 6‐month mobility.
Conclusion: PT immediately after hip fracture surgery is beneficial. The effects of later therapy on mobility were difficult to assess because of limitations of the data. Well‐designed randomized, controlled trials of the effect of varying schedules and amounts of therapy on functional status after hip fracture would be informative.
The choice of inhaler device for bronchodilator reversibility is crucial since suboptimal inhalation technique may influence the result. On the other hand, bronchodilator response also varies from ...time to time and may depend on patient characteristics. In this study, patients with airway obstruction (forced expiratory volume in 1 second FEV1/forced vital capacity FVC ratio <70% in chronic obstructive pulmonary disease COPD; <80% in asthma) were included (n=121, age: 57.8±17.3 years). Bronchodilator reversibility (American Thoracic Society/European Respiratory Society criteria) was tested in patients with COPD (n=63) and asthma and COPD overlap syndrome (ACOS; n=12). Forty-six asthmatics served as controls. Reversibility was tested with 400 µg salbutamol dry powder inhaler (Buventol Easyhaler, Orion Pharma Ltd, Espoo, Finland). Demographic data and patients' perceptions of Easyhaler compared with β2-agonist pressurized metered dose inhalers (pMDIs) were analyzed. American Thoracic Society/European Respiratory Society guideline defined reversibility was found in 21 out of 63 COPD patients and in two out of 12 ACOS patients. Airway obstruction was more severe in COPD patients as compared with controls (mean FEV1 and FEV1% predicted both P<0.0001). Average response to salbutamol was significantly lower in COPD patients compared with asthma controls (P<0.0001). Reversibility was equally often found in smokers as in never-smokers (33% vs 34%). Nonreversible COPD patients had higher mean weight, body mass index, and FEV1/FVC compared with reversible COPD patients. Most patients preferred Easyhaler and defined its use as simpler and more effective than use of a pMDI. Never-smokers and patients with asthma experienced Easy-haler somewhat easier to use than smokers and patients with COPD. In conclusion, a substantial part of patients with COPD or ACOS showed reversibility to salbutamol dry powder inhaler. Nonreversible patients with COPD were characterized by higher weight and body mass index, and a higher FEV1/FVC ratio. Most patients preferred Easyhaler compared with a pMDI.
BACKGROUND: Limited information is available on preoperative status and risks for complications for older patients having surgery for hip fracture. Our objective was to identify potentially ...modifiable clinical findings that should be considered in decisions about the timing of surgery.
METHODS: We conducted a prospective cohort study with data obtained from medical records and through structured interviews with patients. A total of 571 adults with hip fracture who were admitted to 4 metropolitan hospitals were included.
RESULTS: Multiple logistic regression was used to identify risk factors (including 11 categories of physical and laboratory findings, classified as mild and severe abnormalities) for in‐hospital complications. The presence of more than 1 (odds ratiol OR 9.7, 95% confidence interval CI 2.8 to 33.0) major abnormality before surgery or the presence of major abnormalities on admission that were not corrected prior to surgery (OR 2.8, 95% CI 1.2 to 6.4) was independently associated with the development of postoperative complications. We also found that minor abnormalities, while warranting correction, did not increase risk (OR 0.70, 95% CI 0.28 to 1.73).
CONCLUSIONS: In this study of older adults undergoing urgent surgery, potentially reversible abnormalities in laboratory and physical examination occurred frequently and significantly increased the risk of postoperative complications. Major clinical abnormalities should be corrected prior to surgery, but patients with minor abnormalities may proceed to surgery with attention to these medical problems perioperatively.
This two-year-study was aimed to provide results on the effect of nitrogen, phosphorus, potassium and magnesium fertilizer treatments (control, NP, NPK, NPKMg) on vegetative and generative features ...of the sweet cherry cultivar ‘Carmen’. Examinations were performed in an orchard planted in 2012 on Prunus mahaleb rootstock with spacing of 5 x 2.5 m. All treatments improved the vegetative features of the sweet cherry trees in both years of 2016 and 2017. Fertilizer treated trees increased trunk cross section area (TCSA) with 51.3-63.1%, while control trees showed 48.3% trunk growth increase. Yields of control trees were lower in both years (5.9-7.2 kg/tree), than that of the fertilized trees (7.8-11.3 kg/tree). Treatments also increased the phosphorus (16-22%), magnesium (12-20%) and potassium content (3.5-18%) of the fruits compared to control treatments.
Summary
Allergic airway disease can be refractory to anti‐inflammatory treatment, whose cause is unclarified. Therefore, in the present experiment, we have tested the hypothesis that co‐exposure to ...lipopolysacharide (Lps) and allergen results in glucocorticoid‐resistant eosinophil airway inflammation and hyper‐responsiveness (AHR). Ovalbumin (Ova)‐sensitized BALB/c mice were primed with 10 μg intranasal Lps 24 h before the start of Ova challenges (20 min on 3 consecutive days). Dexamethasone (5 mg/kg/day) was given on the last 2 days of Ova challenges. AHR, cellular build‐up, cytokine and nitrite concentrations of bronchoalveolar lavage fluid (BALF) and lung histology were examined. To assess the role of iNOS‐derived NO in airway responsiveness, mice were treated with a selective inhibitor of this enzyme (1400W) 2 h before AHR measurements. More severe eosinophil inflammation and higher nitrite formation were found in Lps‐primed than in non‐primed allergized mice. After Lps priming, AHR and concentrations of T‐helper type 2 cytokines in BALF were decreased, but still remained significantly higher than in controls. Eosinophil inflammation was partially, while nitrite production and AHR were observed to be largely dexamethasone resistant in Lps‐primed allergized animals. 1400W effectively and rapidly diminished the AHR in Ova‐sensitized and challenged mice, but failed to affect it after Lps priming plus allergization. In conclusion, Lps inhalation may exaggerate eosinophil inflammation and reduce responsiveness to anti‐inflammatory treatment in allergic airway disease.
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