The University of Georgia (USA) is partnering with the University of Padova (Italy) for a dual Master’s degree program in sustainable agriculture, promoting collaboration on some of the biggest challenges facing agriculture today. This innovative program which was launched during 2016 provides students with outstanding training and a unique opportunity to learn about the challenges, opportunities, and leading edges of precision agriculture on another continent – an experience which will serve graduates well when they enter the job market in an increasingly global economy. This paper presents the goals of the program, the curriculum, and describes the opportunities available to prospective students. In addition it describes the process of developing the dual degree which can be used as guide by others wishing to develop similar programs.

The main goal of this study was assessing the technological and agronomic performances of a centre pivot Variable Rate Irrigation (VRI) system. The study was conducted in 2015 on a 16-ha field cultivated with maize. Irrigation was scheduled in three Management Zones according to data provided by a real-time monitoring system based on an array of soil moisture sensors. First results demonstrated the potential benefits of the VRI system on irrigation performance however a multiyear comparison is requested for evaluating the response to climate variability. VRI resulted in yields comparable to the business-as-usual regime but through a noticeable reduction in irrigation volumes.

We have studied the infrared absorption by the OD stretching, vOD(D2O), and D2O rotational, vR(D2O), vibrations of fully deuterated ice II and ice IX at lo K, and the absorption by OD stretching vibrations, vOD (HDO), of HDO molecules isolated in ices Ih, II, and IX at 10 K. Calculations of the frequencies and relative intensities of the zero-wave-vector normal vOD(D2O) vibrations of ices II and IX have allowed the vOD(D2O) absorption to be assigned. Each component of the band is broad, even at 10 K, most probably because of Fermi resonance between the fundamental OD stretching vibrational states and the isoenergetic continuum of high-order overtone and combination states of the lattice modes. This work has yielded the most complete interpretation yet achieved of an infrared band due to the OH or OD stretching vibrations of a phase of ice.

The far-infrared absorption by the translational vibrations of H2O and D2O ices Ih and Ic at 4.3 K has been measured, and has revealed differences between the spectra of ices III and Ic for the first time.

Papers describing this work in full have been published in Journal of Chemical Physics, Vol. 67, No. 4, 1977, p. 1311-18, and Vol. 67, No. 6, 1977, p. 2445-48.

Detailed mid- and far-infrared spectra have been recorded for authenticated samples of several clathrate hydrates with the two main structures, I and II, at temperatures between 150 and 4 K. The systems are complicated, yet a detailed analysis of the many interesting spectral features is required before reliable, detailed information can be obtained. Consequently only rather general conclusions can be drawn at present.

The mid-infrared spectra have been recorded for the structure I hydrates and deuterates of ethylene oxide, trimethylene oxide, and cyclopropane, and the structure II hydrate and deuterate of trimethylene oxide, all at 100 K. The OD stretching vibrations of isolated HDO molecules, vOD (HDO), and of the fully deuterated forms, vOD(D2O), have also been recorded for cyclopropane and trimethylene oxide structure I hydrates at 40 K, and the absorption by the guest molecules has been studied for all of the structure I hydrates at temperatures down to 40 K.

The absorption by the water molecules at 100 K is similar to that in ice, with frequencies that vary in the expected way with the lattice parameter and, hence, the hydrogen bond lengths. The shapes of the vOH(H2O)vOD(D2O), and vR(D2O) bands are essentially the same for structures I and II, while the vOD(D2O) band varies only slightly and depends more on the guest molecule than on the structure. The water absorption changed only slightly when the samples were cooled from 100 to 40 K.

The vOD(HDO) bands provide clear evidence that the distribution of hydrogen bond lengths in cyclopropane hydrate differs from those in ethylene oxide and trimethylene oxide structure I hydrates, even though powder X-ray methods indicate that the three hydrates are isostructural. The difference is attributed to an interaction between the hydrogen bonds and the dipole moment of the guest which is too irregular to be sensed by powder X-ray methods.

Some absorption bands of the guest molecules are visible in the spectra of structure I hydrates and, as expected, fewer are visible in the spectra of structure II hydrates, which have a higher water-to-guest ratio. For both structures more guest bands are visible in the spectra of deuterates since the D2O absorption is weaker than that of H2O. The guest bands are single in most cases, with half-widths of 1 to 5 cm-1 for ethylene oxide and cyclopropane and 5 to 15 cm-1 for trimethylene oxide in its deuterates of both structures. One band of ethylene oxide at 100 K and below is a doublet, and one degenerate and one non-degenerate vibration of cyclopropane yields a doublet at 40 K. This must mean that there are two non-equivalent positions for the guest molecule in the tetrakaidecahedral cage of the structure I hydrate at these temperatures.

Far infrared spectra have been recorded of the structure I hydrates of ethylene oxide, cyclopropane, trimethylene oxide, and xenon, and of the structure II hydrates of trimethylene oxide, cyclopropane, tetrahydrofuran, cyclobutanone, and 1,3-dioxolane, all at 4.3 K. The spectra of the hydrates and corresponding deuterates have enabled the absorption by the rotational vibrations of the guest molecules in the cage to be identified. The absorption above 100 cm-1 by the translational vibrations of the water molecules is significantly different for the two structures, but is rather insensitive to the guest molecule within one structure.

A careful search was made for evidence of the transition in trimethylene oxide structure I hydrate at which the guest molecules partly order, that was detected by Davidson from dielectric studies. No spectral changes due to the transition were detected.

Papers describing this work have been published in Canadian. Journal of Chemistry, Vol. 51, No. 8, 1973, p. 1159-68; Vol. 53, No. 1, 1975, p. 71-75; Vol. 55, No. 10, 1977, p. 1777-85. A further paper is accepted for publication in Journal of Chemical Physics and others arc in preparation.

The introduction of herbicide-resistant crops and postemergence herbicides with a wide action spectrum shifted the research focus from how to when crops should be treated. To maximize net return of herbicide applications, the evolution of weed–crop competition over time must be considered and its effects quantified. A model for predicting the yield trend in relation to weed removal time, considering emergence dynamics and density, was tested on data from glyphosate-resistant soybean grown in cropping systems in Italy and Argentina. Despite an ample variation of weed emergence dynamics and weed load in the four trials, the model satisfactorily predicted yield loss evolution. The estimated optimum time for weed control (OTWC) varied from about 18 d after soybean emergence in Argentina to 20 to 23 d in Italy, with time windows for spraying ranging from 14 to 28 d. Within these limits a single glyphosate application ensures good weed control at low cost and avoids side effects like the more probable unfavorable weed flora evolution with double applications and the presence of residues in grains. Despite the apparent simplicity of weed control based on nonselective herbicides, the study outlines that many variables have to be considered to optimize weed management, particularly for the time evolution of the infestation and, subsequently, a proper timing of herbicide application.

This study examines the factors that determine the likelihood of submitting a potentially fraudulent prevented planting claim. A theoretical model is developed and the theoretical predictions are empirically verified by utilizing a binary choice model and crop insurance data from the southern United States. The empirical results show that insured producers with higher prevented planting coverage, lower dollar value of expected yield, and a history of submitting prevented planting claims are more likely to submit an anomalous prevented planting claim. The empirical model also suggests revenue insurance plans may be more vulnerable to prevented planting fraud than the traditional yield-based insurance plan. Results of this study can be valuable to compliance offices in their efforts to find “indicators” of fraudulent behavior in crop insurance, especially with regard to prevented planting.

To evaluate measles incidence and its relevant changes over a 14-year period (2000–2014), we analysed data from the regional hospital discharge database on children and adults hospitalized in Tuscany, Italy. A total of 181 paediatric and 413 adult cases were identified. Despite all the efforts towards regional measles elimination, we observed that the overall measles hospitalization rates for children and adults living in Tuscany globally increased from 0·45 to 0·85/100 000 during the study period (P = 0·001) showing fluctuations due to periodic measles outbreaks. Data stratified by age group showed that the hospitalization rate significantly increased in young adults over the study period, confirming an increase in susceptibility to measles in this subpopulation. Conversely, no statistically significant difference was observed in the hospitalization rate in the other age groups. However, children aged <1 year still exhibit the highest hospitalization rate. Pneumonia represented the most common complication in both the adult and children subsets. No death was reported. Measles still represents a public health problem, and national strategies should be implemented, focusing on emergent susceptible subsets, such as infants and young adults.

This article analyzes anomalous patterns of agent, adjuster, and producer claim outcomes and determines the most likely pattern of collusion that is suggestive of fraud, waste, and abuse in the federal crop insurance program. Log–linear analysis of Poisson-distributed counts of anomalous entities is used to examine potential patterns of collusion. The most likely pattern of collusion present in the crop insurance program is where agents, adjusters, and producers nonrecursively interact with each other to coordinate their behavior. However, if a priori an intermediary is known to initiate and coordinate the collusion, a pattern where the producer acts as the intermediary is the most likely pattern of collusion evidenced in the data. These results have important implications for insurance program design and compliance.

The present paper is about the estimation of lattice deformation from data collected from manufactures directly on site. The aim here is to give evidence that the concept of the Mean Equivalent Lattice (MEL), when applied to “on site X-Ray Diffraction” is the basis for a reliable qualification of the material rheology to external solicitations. Such method allows for the identification of lattice deformations without resorting to the computation of the residual stress with using the elasticity constants (i.e. tensile, shear and rigidity constants E, μ, ν); these elasticity constants descend from the classical theory of solid mechanics, where the continuum mechanics and the material isotropic model are the fundaments. Any MEL deformation is instead related to the variation of the d-spacing among lattice planes which are connected to the anisotropic atomic arrangement. So the macroscopic scale is constituted by a number of MELs and related boundaries. The recent on site X-ray diffraction technology may offer effective and easy solutions, with a significant impact on reliability of results, simplification, economy and time consuming.

Assortative mating for age and several anthropometric characteristics is considered in a sample of 68–70 husband-wife pairs from a rural Zapotec-speaking community in the Valley of Oaxaca in southern Mexico. Conditions in the community with a population of approximately 1700 indicate chronic, mild-to-moderate undernutrition as reflected in high infant mortality rates, smaller body size of school children, and delayed biological maturation. Phenotypic assortative mating, as expressed in husband-wife correlations, is significant for age (r = 0·96), stature (r = 0·35) and grip strength (r = 0·29), but is not significant for body weight (r = 0·01), arm circumference (r = 0·07), the estimated midarm muscle circumference (r = 0·003), Quetelet's index (r = 0·02), and the ponderal index (r = 0·11). Controlling for age of husband and wife reduces the correlations for stature (r = 0·24) and grip strength (r = 0·12), but increases those for arm circumference (r = 0·21) and estimated midarm muscle circumference (r = 0·16). Grouping the spouses into younger (under 30 years of age) and older (30 years and older) results in significant spouse correlations for age, stature, arm circumference and estimated midarm muscle circumference in the younger group and for only age and fatness in the older group.

Summary

Background and objective: To evaluate the effects of sevoflurane and desflurane in combination with intravenous remifentanil on time for discharge from the postanaesthesia care unit and need for postanaesthesia care unit management after elective laparoscopic cholecystectomy. Methods: 231 ASA Grade I–II patients, undergoing elective laparoscopic cholecystectomy in seven University teaching hospital, were randomly allocated to receive a desflurane–remifentanil (n = 105) or sevoflurane–remifentanil (n = 126) anaesthetic. A blinded observer recorded times for emergence and postanaesthesia care unit discharge (achievement of an Aldrete score ≥9), number of patients eligible for postanaesthesia care unit discharge when exiting the operating room and occurrence of adverse events. Results: Intraoperative cardiovascular stability was similar in the two groups. Emergence, response and extubation occurred earlier after desflurane (5.4 ± 3 min, 5.5 ± 3 min and 7.5 ± 4 min) than sevoflurane (6.6 ± 3.5 min, 7.2 ± 4 min and 9.1 ± 4.2 min) (P = 0.0005, 0.05 and 0.003, respectively). Postanaesthesia care unit bypass was possible in 44 desflurane–remifentanil patients (41%) and 55 sevoflurane– remifenatnil patients (43%) (P = 0.69), while postanaesthesia care unit discharge occurred after 46 min (25th–75th percentiles: 18–40 min) with desflurane and 64 min (25th–75th percentiles: 20–50 min) with sevoflurane (P = 0.04). Postoperative nausea and vomiting was observed in 40 desflurane–remifentanil patients (36%) and 53 sevoflurane–remifentanil patients (42%) (P = 0.42). Conclusions: Both the desflurane–remifentanil and sevoflurane–remifentanil combinations provide a similarly adequate intraoperative cardiovascular stability. Emergence and postanaesthesia care unit discharge were faster with desflurane–remifentanil than sevoflurane–remifentanil, but this was not associated with a larger proportion of postanaesthesia care unit bypass, confirming that no clinically relevant differences are present between the two agents.

Background and objective: The aim of this prospective, randomized study was to compare the preparation and discharge times, the side-effects and patient satisfaction after gynaecological outpatient procedures performed using either spinal block or total intravenous anaesthesia with propofol and remifentanil.

Methods: With Ethics Committee approval and written informed consent, 40 healthy females scheduled for hysteroscopic ablation of endometrial neoplasm were randomly allocated to receive either a spinal block with bupivacaine 0.5% hyperbaric solution 10 mg (n = 20) or total intravenous anaesthesia with propofol and remifentanil (n = 20). Preparation and discharge times, as well as occurrence of untoward events and anaesthesiarelated costs, were recorded.

Results: The median (range) preparation time was 7 (7–10) min with general anaesthesia, and 11 (7–21) min with spinal block (P = 0.00005). No differences in discharge time from the postanaesthesia care unit and incidence of hypotension or bradycardia, or both, were reported between the two groups. Hospital discharge times were 156 (101–345) min after general anaesthesia and 296 (195–720) min after spinal anaesthesia (P = 0.0005). Acceptance of the anaesthesia technique was better after general (100%) than after spinal anaesthesia (75%) (P = 0.04). No differences in total costs were reported between spinal block (€155 (€117–€224)) and propofol-remifentanil general anaesthesia (€143 (€124–€203) (P = 0.125)).

Conclusions: Accurate titration of short-acting intravenous anaesthetic drugs such as propofol and remifentanil results in shorter preparation times and earlier home discharge after outpatient gynaecological procedures compared with spinal anaesthesia with hyperbaric bupivacaine 10 mg, with better patient acceptance and no increased costs.

Background and objective: To evaluate preparation and discharge times as well as the anaesthesia-related costs of out-patient knee arthroscopy performed with a combined sciatic-femoral nerve block, or a propofol-remifentanil general anaesthetic.

Methods: With Ethics Committee approval and written informed consent, 40 healthy patients were premedicated with intravenous midazolam (0.05 mg kg−1) and ketoprofen (50 mg). They were then randomly allocated to receive either a combined sciatic-femoral nerve block with 25 mL mepivacaine 2% (15 mL for the femoral nerve, 10 mL for the sciatic nerve) (PNB group, n = 20), or a general anaesthetic with a continuous intravenous infusion of remifentanil (0.1–0.3 μg kg−1min−1) and propofol (target plasma concentration 2–4 μg mL−1) with a laryngeal mask airway (GA group, n = 20).

Results: The median (range) preparation time was 16 (10–28) min in the PNB group and 13 (8–22) min in the GA group (P = 0.015). Ten PNB patients were directly discharged to the day-surgery unit after the procedure as compared with one GA patient (P = 0.003). Discharge from the postanaesthesia care unit (PACU) required 5 (5–20) min in the PNB group and 23 (7–95) min in the GA group (P = 0.001). Home discharge criteria were fulfilled after 277 (150–485) min in the PNB group and 170 (100–400)min in the GA group (P = 0.005). Costs related to the time spent in the PACU were lower for the PNB group (€1.10, range 0–22) compared with the GA group (€30, range €0–176) (P = 0.0005). There were no differences in total costs: PNB group €158 (range €105–194) versus GA group €160 (range €101–238) (P = 0.61).

Conclusions: In patients undergoing out-patient knee arthroscopy, the length of stay in the PACU can be shorter after a sciatic-femoral nerve block with a small volume of mepivacaine 2% compared with a propofol-remifentanil anaesthetic, and there is an increased likelihood that they will bypass the first phase of the postoperative recovery.

The interactions between self-interstitials (I's) produced by 20 keV silicon implantation, and substitutional carbon in silicon have been studied using a Si1-yCy layer interposed between a near surface I source and a deeper B spike used as a marker for the I concentration. The Si1-yCy layer behaves as a filtering membrane for the interstitials flowing towards the bulk. This trapping ability is related to the total C amount in the Si1-yCy membrane. Substitutional carbon atoms interacting with self-interstitials are shown to trap I's, to be removed from their substitutional sites, and to precipitate into the C-rich region. After precipitation, C atoms are not able to further trap injected self-interstitials. The atomistic mechanism leading to Si-interstitial trapping has been investigated by developing a simulation code describing the migration of injected interstitials. By a comparison with the experimental data it was possible to derive quantitative indications on the trapping mechanism. It is shown that one Si-interstitial is able to deactivate about two C traps by means of interstitial trapping and C-clustering reactions.

In this work we investigated the diffusion and clustering of supersaturated substitutional carbon 200nm thick SiGeC layers buried under a silicon cap layer of 40nm. The samples were annealed in inert (N2) or oxidizing (O2) ambient at 850°C for times ranging from 2 to 10 hours. The silicon self-interstitial (I) flux coming from the surface under oxidation enhances the C diffusion with respect to the N2 annealed samples. In the early stages of the oxidation process, carbon escape by diffusion across the layer/cap interface dominates. This phenomenon saturates after an initial period (2-4h) which depends on the C concentration. This saturation is due to the formation and growth of C containing precipitates which are promoted by the I injection and act as a sink for mobile C atoms. The competition between clustering and diffusion is discussed for two different C concentrations.

The effect of annealing silicon capped pseudomorphic Si0.7865Ge0.21C0.0035 or Si0.998C0.002 layers on silicon substrates in nitrogen or oxygen at 850°C was examined using x-ray diffraction (XRD) and secondary ion mass spectrometry (SIMS). Most substitutional carbon is lost from the alloy layers due to carbon out-diffusion rather than from precipitation. The carbon is found to diffuse more rapidly out of the SiGeC layer than the SiC layer after nitrogen and the carbon is found to leave the sample entirely, an effect that is enhanced by oxidation and thin cap layers. All substitutional carbon can be removed from the sample in some cases implying negligible formation of silicon-carbon complexes. Furthermore, it is found that each injected silicon interstitial atom due to oxidation causes the removal of one additional carbon atom for the SiGeC layer.

The results of a systematic investigation by transmission electron microscopy (TEM), cathodoluminescence (CL), Rutherford backscattering (RBS), X-ray diffraction and topography and scanning force microscopy (SFM) techniques on several InGaAs/InP compressive and tensile strained layers covering the misfit range from −2.3 to 1.5×10−2 and grown by the metal organic vapor phase epitaxy (MOVPE) technique are reported. In compressively strained films the same dependence for the residual strain vs the film thickness as for the InGaAs/GaAs is found whereas a different strain release rate and different extended defects are found in tensile stressed InGaAs alloy. In particular in tensile stressed samples, grooves, planar defects and cracks are present in addition to the interfacial network of misfit dislocations. The correlation between the observed planar defects and the mechanisms of strain relaxation in the case of tensile strained layers is discussed.

Axillary brachial plexus block using 20 mL of 0.75% ropivacaine or 2% mepivacaine was compared in a prospective, randomized, double-blind study of two groups of 15 patients. The times to onset of sensory and motor block and to resolution of motor block, as well as the time to onset and degree of post-operative pain were recorded by an observer blinded to the identity of drug. Times to onset of sensory block were similar in the two groups (ropivacaine 10 min, mepivacaine 8 min). Resolution of motor block in the operated hand and the time to first requirement of post-operative analgesia occurred later with ropivacaine (9 h 50 min and 10 h) than with mepivacaine (3 h 50 min and 6 h), P<0.01 for both measurements. Nine patients who received ropivacaine and two patients who received mepivacaine did not require further post-operative analgesia (P<0.05). Ropivacaine is less toxic than other long-acting local anaesthetics, and 0.75% ropivacaine may be better for brachial plexus block when fast onset is required and prolonged pain relief is useful.

We describe a case of transient neurological deficit that occurred after unilateral spinal anaesthesia with 8 mg of 1% hyperbaric bupivacaine slowly injected through a 25-gauge pencil-point spinal needle. The surgery and anaesthesia were uneventful, but 3 days after surgery, the patient reported an area of hypoaesthesia over L3–L4 dermatomes of the leg which had been operated on (loss of pinprick sensation) without reduction in muscular strength. Sensation in this area returned to normal over the following 2 weeks. Prospective multicentre studies with a large population and a long follow-up should be performed in order to evaluate the incidence of this unusual side effect. However, we suggest that a low solution concentration should be preferred for unilateral spinal anaesthesia with a hyperbaric anaesthetic solution (if pencil-point needle and slow injection rate are employed), in order to minimize the risk of a localized high peak anaesthetic concentration, which might lead to a transient neurological deficit.