Local Modeling by Adapting Source Calibration Models to Analyte Shifted Target Domain Samples Without Reference Values.

Spectral multivariate calibration aims to derive models characterizing mathematical relationships between sample analyte amounts and corresponding spectral responses. These models are effective at predicting target domain sample analyte amounts when target samples are within the analyte and spectral calibration source domain. Models fail when target samples shift (analyte amounts and/or spectra) from the original calibration domain model. A total recalibration solution requires acquisition of new sample reference values and spectra. However, obtaining enough reference values to distinguish the target domain may be challenging or expensive. A simpler approach adapts the original model to the target domain using target sample spectra without analyte reference values (unlabeled). Analytical chemists have developed several machine learning algorithms using unlabeled regression domain adaptation processes. Unfortunately, prediction accuracy declines for these methods depending on how much the target domain analyte distribution has shifted from the calibration distribution, and regression transfer learning methods are instead needed. Regression domain adaptation and transfer learning are often referred to as model updating in analytical chemistry, but regression domain adaptation only applies to spectral shifts. The regression transfer learning method presented in this paper named null augmentation regression constant analyte (NARCA) leverages unlabeled repeat spectra of a single target sample to update an original calibration model to the shifted target domain sample. With sample repeat spectra, the analyte amount can be assumed constant or nearly constant for NARCA and because models are formed for one sample, NARCA operates as a local modeling method. The performance of NARCA as a regression transfer learning method is evaluated using five near-infrared data sets.

Lower limb asymmetry in mechanical muscle function: A comparison between ski racers with and without ACL reconstruction.

Due to a high incidence of anterior cruciate ligament (ACL) re-injury in alpine ski racers, this study aims to assess functional asymmetry in the countermovement jump (CMJ), squat jump (SJ), and leg muscle mass in elite ski racers with and without anterior cruciate ligament reconstruction (ACL-R). Elite alpine skiers with ACL-R (n = 9; 26.2 ± 11.8 months post-op) and uninjured skiers (n = 9) participated in neuromuscular screening. Vertical ground reaction force during the CMJ and SJ was assessed using dual force plate methodology to obtain phase-specific bilateral asymmetry indices (AIs) for kinetic impulse (CMJ and SJ phase-specific kinetic impulse AI). Dual x-ray absorptiometry scanning was used to assess asymmetry in lower body muscle mass. Compared with controls, ACL-R skiers had increased AI in muscle mass (P < 0.001), kinetic impulse AI in the CMJ concentric phase (P < 0.05), and the final phase of the SJ (P < 0.05). Positive associations were observed between muscle mass and AI in the CMJ concentric phase (r = 0.57, P < 0.01) as well as in the late SJ phase (r = 0.66, P < 0.01). Future research is required to assess the role of the CMJ and SJ phase-specific kinetic impulse AI as a part of a multifaceted approach for improving outcome following ACL-R in elite ski racers.

Product state and speed distributions in photochemical triple fragmentations.

The clearest dynamical signature of a roaming reaction is a very cold distribution of energy into the rotational and translational degrees of freedom of the roaming donor fragment (e.g. CO) and an exceptionally hot vibrational distribution in the roaming acceptor fragment (e.g. H2, CH4). These signatures were initially identified in joint experimental/theoretical investigations of roaming in H2CO and CH3CHO and are now used to infer the presence of roaming mechanisms in other photodissociation reactions. In this paper we construct a phase space theory (PST) model of triple fragmentation (3F) and show that the dynamical signature of 3F is similar to that of the roaming donor fragment. The PST model starts with a calculation of two-body fragmentation (2F) of a generic molecule, ABC into AB + C. Every AB fragment with sufficient energy to undergo subsequence spontaneous dissociation is allowed to dissociate and the PST distribution of energy into A + B products is calculated for every initial AB state. Using CH3CHO --> HCO + CH3 --> H + CO + CH3 as an example, we calculate that the energy disposal into the rotational and translational degrees of freedom of the 3F products is very low, and is similar to the dynamical signature expected for production of CO via a roaming mechanism. We compare the 3F PST model with published experimental data for photodissociation of CH3CHO and CH3OCHO at energies above the 3F threshold.

The liver antioxidant status of fattening lambs is improved by naringin dietary supplementation at 0.15% rates but not meat quality.

Twenty Assaf lambs fed barley straw plus a concentrate alone (CONTROL group) or enriched with naringin (1.5 g/kg DM, NARINGIN group) were used to assess the effect of this polyphenolic compound on meat quality attributes. Serum samples were collected for 7 weeks, then the animals were slaughtered and the livers and longissimus thoracis et lumborum muscles extracted for analysis. Triacylglycerol levels in the serum samples tended to show (P = 0.087) lower average values for the NARINGIN group when compared with the CONTROL, but no differences were observed when the meat was analysed for the intramuscular fat content. Lower thiobarbituric acid-reactive substances procedure (TBARS) values (P < 0.001) in the liver of the NARINGIN group were detected, probably as a consequence of naringenin accumulation in this organ. No significant differences were observed in the meat samples concerning TBARS or colour evolution during refrigerated storage, as not enough naringenin would have reached the muscle. Independent of naringin administration, the low levels of the most atherogenic oxysterols must be highlighted as the most important quality score in the lamb meat samples studied.

The effect of diets supplemented with thyme essential oils and rosemary extract on the deterioration of farmed gilthead seabream (Sparus aurata) during storage on ice.

The effect on quality were assessed for gilthead seabream fed five different diets: control (basal diet); BHT (basal diet with 200mgkg-1 of butylated hydroxytoluene); rosemary (basal diet with 600mgkg-1 of rosemary extract -Rosmarinus officinalis); carvacrol (basal diet with 500mgkg-1 of essential oil of Thymbra capitata, carvacrol chemotype); and thymol (basal diet with 500mgg-1 of essential oil of Thymus zygis, subspecies gracilis, thymol chemotype). After 18weeks of experimentation, the animals were stored on ice at 4°C for 0, 7, 14, and 21days. Physical-chemical, microbiological and sensory analyses were carried out at each sampling point to determine the degree of deterioration in the gilthead seabream. Lower indices of oxidation were observed in animals who were administered feeds supplemented with BHT, carvacrol and (to a lesser degree) rosemary. Lower bacteria counts were observed for the BHT and thymol groups, in addition to a slower deterioration in terms of sensory perception. Accordingly, the addition of natural antioxidants to the diet may have an added effect on fish quality, delaying post mortem deterioration.

Effect of thyme essential oils (Thymus hyemalis and Thymus zygis) and monensin on in vitro ruminal degradation and volatile fatty acid production.

The effect of the essential oils of thyme on the in vitro ruminal degradability of a barley seed/alfalfa hay substrate was studied. Two essential oils were used, one from Thymus hyemalis (TH), rich in carvacrol, and the other from Thymus zygis (TZ), rich in thymol. Four experimental treatments of in vitro degradability, using the Daisy II(200/220) incubator, were conducted including a negative control (CO), a positive control at 7.5 microg/mL of monensin (MO), and two treatments with essential oils (TH or TZ) at 1.35 microL/mL. The material was incubated at 39.5 degrees C for various lengths of time. At each time, the disappearance of dry matter, crude protein, and neutral detergent fiber was measured. Volatile fatty acids (VFAs) were determined after 48 h of incubation. CO and MO provided (p < 0.01) higher values of potential degradability (a + b) of DM than the TH and TZ treatments (72.6 and 70.8 vs 53.2 and 48.2%, respectively). Also, crude protein degradability was lowest in the essential oil treatments. The CO treatment showed the highest potential degradability of NDF. The values of VFA production obtained (p < 0.001) with CO and MO treatments were higher than those obtained with TH and TZ treatments (21.0 and 19.1 vs 11.2 and 10.1 mM). The essential oils decreased the molar proportion of propionate, increasing the acetate/propionate ratio. In conclusion, the effects of essential oils at assayed doses would not be nutritionally beneficial to the ruminal energetic metabolism.

Interpolated potential energy surfaces: How accurate do the second derivatives have to be?

A global potential energy surface for the water dimer is constructed using the modified Shepard interpolation scheme of Collins et al. According to this interpolation scheme, the energy at an arbitrary geometry is expressed as a weighted sum of Taylor series expansions from neighboring data points, where the energy and derivative data required are obtained from ab initio calculations. For some ab initio methods, errors are introduced into the second derivative matrix, either by numerical differencing of ab initio energies or numerical integration during the ab initio calculation. Therefore, we test the accuracy required of the second derivative data by truncation of the exact second derivatives to a series of approximate second derivatives, and assess the effect on the results of a quantum diffusion Monte Carlo (QDMC) simulation. Our results show that the calculated zero-point energy and wave function histograms converge to within the numerical uncertainty of the QDMC simulation by inclusion of either three significant figures or three decimal places in the second derivatives.

Volatile components in aqueous essence and fresh fruit of Cucumis melo cv. Athena (muskmelon) by GC-MS and GC-O.

A comparative study between the aromatic profile of muskmelon aqueous essence and the puree of fresh fruit was carried out using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O). Results obtained show a total of 53 components quantified in the essence and 38 in the fresh fruit. In addition, four new components are described for the first time as contributors to the aromatic profile of muskmelon including 2-methyl-3-buten-2-ol, 2,3-butanediol, methyl 3-phenylpropionate, and ethyl 3-phenylpropionate (found only in the puree of the fruit). The olfactometric analysis revealed the presence of 25 components with aromatic activity. Esters, alcohols, and one sulfur component [ethyl 3-(methylthio)propionate] appear to be the most important contributors to the essence aroma. The aromagram of fresh fruit is richer in high molecular weight components, which have not yet been positively identified and do not present detectable peaks in the flame ionization detector.

Aromatic profile of aqueous banana essence and banana fruit by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O).

Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O) were used to determine the aromatic composition and aroma active components of commercial banana essence and fresh banana fruit paste. Totals of 43 and 26 compounds were quantified in commercial banana essence and fresh banana fruit paste, respectively. Five new components in commercial banana essence were identified as methyl butyrate, 2,3-butanediol diacetate, 2-hydroxy-3-methylethylbutyrate, 1-methylbutyl isobutyrate, and ethyl 3-hydroxyhexanoate. A total of 42 components appear to contribute to the aromatic profile in banana. Isoamyl acetate, 2-pentanol acetate, 2-methyl-1-propanol, 3-methyl-1-butanol, 3-methylbutanal, acetal, isobutyl acetate, hexanal, ethyl butyrate, 2-heptanol, and butyl butyrate had high concentrations and were most detected by GC-O panelists in the commercial banana essence. Volatile components found only in fresh banana fruit paste that were detected by aroma panelists include E-2-hexenal, limonene, and eugenol.

Intraoperative assessment of atracurium-induced neuromuscular block using double burst stimulation.

Paired train-of-four (TOF) and double burst stimuli (DBS) were administered to the ulnar nerve at the wrist in 25 patients (group 1) paralysed with atracurium 0.5 mg kg-1; responses were measured mechanically (except every third DBS response which was manually evaluated). Another 30 patients (group 2) received a DBS every 60 s. A post-tetanic count (PTC) was performed when the first response (D1) was palpated. There was a significant correlation between the twitch heights of the first TOF response (T1) and D1 and likewise between the twitch heights of both second responses (r = 0.9; P less than 0.001), but there was a significant difference in regression coefficients of these two correlations (P less than 0.001). D1 was palpable first with a median PTC of 7. Our results showed that palpation of a single response implied a satisfactory level of paralysis. DBS may be useful for intraoperative clinical monitoring of neuromuscular block.

Clinical approach to treatment of otitis media.

The author presents his experience of 10 years of practice with the treatment of otitis media. He expresses concern for the inconsistencies between articles written recommending treatment protocols for otitis media and actual clinical results from using those treatment protocols. Otitis media varies in its appearance from patient to patient, with its association to other continuous structures and other organ systems making it a challenging disease to correct and cure. Treatment must be tailor-made to fit the patient, and the physician needs to consider other professional opinions and emphasize follow-up care.

Neural control of internal anal sphincter function.

The effect on anal tone of electrical stimulation of the presacral (hypogastric) sympathetic nerves has been studied in eight patients during abdominal rectopexy or restorative proctocolectomy. A sharp fall in anal pressure occurred in seven patients (mean fall 59 cmH2O; range 35-80 cmH2O). In one patient given a beta- and alpha-sympathetic blocking drug (labetalol 200 mg) intra-operatively, the anal pressure decreased by 15 cmH2O. These observations show that stimulation of the presacral sympathetic nerves causes relaxation of the internal anal sphincter and implies that these nerves may induce relaxation of the sphincter in vivo. The pathway of the recto-anal reflex has been studied intra-operatively in three patients undergoing rectal excision. The recto-anal reflex is present after presacral nerve blockade and after full mobilization of the rectum, but is abolished by circumferential rectal myotomy. The reflex has a local intramural pathway. This observation validates the assumption that absence of this reflex is a feature of aganglionosis, as in Hirschsprung's disease.

Closed-circuit halothane and enflurane using an in-circle Goldman vaporizer.

A closed-circle absorber system incorporating an in-circle Goldman vaporizer was used to administer halothane or enflurane in oxygen to adult patients. The attained inspired and end-tidal concentrations of volatile agent after a period of stabilization at each vaporizer setting were measured by mass spectrometry. During spontaneous respiration under halothane the ranges of inspired concentrations at settings 1, 11/2 and 2 were respectively 0.5-0.9%, 1.4-2.4% and 3.3-4.5%. corresponding inspired enflurane concentrations at the same settings were 0.8-1.4%, 1.9-2.8% and 3.7-5.0%. IPPV to 5% end-tidal carbon dioxide, although increasing the inspired concentrations slightly, produced considerable increases in end-tidal concentrations. Minimal pre-oxygenation was used to assess the problem of nitrogen accumulation within the circuit. The maximum nitrogen concentration was 56%.

Cimetidine in the prevention of the pulmonary acid aspiration (Mendelson's) syndrome.

Cimetidine 200 mg was given i.v. 1 h before induction of anaesthesia to 20 patients about to undergo emergency surgery. There was an increase in pH of gastric aspirate in all patients (P less than 0.001) and in 80% pH was greater than 2.5 units at the time of induction of anaesthesia. The pH of gastric aspirate continued to increase after induction of anaesthesia and was greater than 4 units in all patients at the time of tracheal extubation and in the early recovery period.

Potency of mixtures of general anaesthetic agents.

The anaesthetic potencies of binary mixtures of the gases argon (Ar), nitrous oxide (N2O) and sulphur hexafluoride (SF6) have been measured using mice. The mixtures SF6-N2O and N2O-Ar showed additive behaviour, whereas the constituents of the mixture SF6-Ar were non-additive, having a smaller total potency than expected. Further experiments on this mixture with Italian Great Newts and on the carbon tetrafluoride mixtures CF4-Ar and CF4-SF6 with mice suggested that the anomalous potencies may arise from specific pulmonary effects associated with the breathing of SF6 accompanied by a high pressure of some other gas.

Effects of zinc-smelter emissions on forest soil microflora.

Within 2 km of a zinc (Zn) smelter in Palmerton, Pennsylvania, near the Lehigh Water Gap, up to 13.5% Zn by weight has been measured in the O2 horizon of the soil, and up to 8% Zn in the A1 horizon. The total numbers of bacteria, actinomycetes, and fungi (measured by dilution plate counts) were greatly reduced in the most severely Zn-contaminated soils compared with control soils. The reduction of microbial populations may be a partial cause of the decreased rate of litter decomposition at Lehigh Gap. Growth of most bacteria from control sites was reduced by 100 to 200 muM Zn, most actinomycetes by 100 muM Zn, and most fungi by 100 to 1000 muM Zn in thin-Pablum extract agar (TPab). All the tested actinomycetes and non-spore-forming bacteria isolated from Zn-contaminated Lehigh Gap soils were Zn-tolerant, growing normally in media containing 600-2000 muM Zn. Most fungi, regardless of source, were capable of at least 50% of normal growth at 700 muM Zn. Zinc-tolerant bacteria, actinomycetes, and fungi were readily isolated from low-Zn soils, suggesting that selection for Zn tolerance may proceed rapidly. Acidophilic Mortierella species have been selectively eliminated near the smelter, apparently because of elevated soil pH. Peryronellaea glomerata (Corda) Goidanich and Coniothyrium spp. were found only in the high-Zn soils.