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This chapter presents a review of the current harvest processes, including the potential for mechanical harvest, of fresh market-quality sweet cherry fruits.

We report on the development of two new mechanically rugged, high light yield transparent ceramic scintillators: (1) Ce-doped Gd-garnet for gamma spectroscopy, and (2) Eu-doped Gd-Lu-bixbyite for radiography. GYGAG(Ce) garnet transparent ceramics offer ρ = 5.8g/cm3, Zeff = 48, principal decay of 8 lp/mm.

SUMMARYA cross-sectional field study was performed to evaluate infection in dogs and cats living on farms withMycobacterium bovis-infected cattle. The purpose was to determine pet infection status and assess their risk to farm families and/or tuberculosis-free livestock. Data and specimens were collected from 18 cats and five dogs from nine participating farms. ELISA testing forM. bovisandM.aviumwas conducted. Fifty-one biological samples were cultured; all were negative forM. bovis, although otherMycobacteriumspecies were recovered. No radiographic, serological or skin test evidence of mycobacterial infection was found. These negative results may be due to the low level ofM. bovisinfection in the cattle and the limited duration of exposure of pets to infected cattle residing on the same farm. No evidence was found to indicate that pets residing onM. bovis-infected Michigan cattle farms pose a risk to humans orM. bovis-free livestock; however, precautionary advice for farm owners was provided.

Vapor-liquid equilibrium measurements have been performed on a set of alcohol/water/salt solutions at atmospheric pressure with a modified Othmer still and a modified Boublik-Benson still. The systems studied are methanol and water with NaCl, NaBr, KCl, and KBr; 1-propanol and water with NaCl, KBr, and NaBr; and 2-propanol with water and NaBr. The measurements are for salt concentrations ranging from infinite dilution to saturation for each water/alcohol solvent mixture

Fifteen 1.25 inch BSTRA balls were scanned with the high energy computed tomography system at LLNL. This system has a resolution limit of approximately 210 microns. A threshold of 238 microns (two voxels) was used, and no anomalies at or greater than this were observed.

A new technique for identifying buried Anti-Personnel Mines is described, and a set of preliminary experiments designed to assess the feasibility of this technique is presented. Analysis of the experimental results indicates that the technique has potential, but additional work is required to bring the technique to fruition. In addition to the experimental results presented here, a technique used to characterize the sensor employed in the experiments is detailed.

This study has investigated the effect of elevating intracellular calcium levels, using an internal calcium ATPase inhibitor, 2,5-di(tert-butyl) hydroquinone (TBQ), on human sperm function. Isolated sperm samples from five fertile donors were incubated in a capacitating media for up to 6 hr. After 0, 3, and 6 hr incubation, sperm were exposed to a range of TBQ concentrations; 100 microM, 10 microM, and 1 microM, for a fixed incubation period of 5 min. Controls were run for each experiment where sperm were incubated for 5 min in the absence of TBQ. Sperm capacitation and the acrosome reaction were monitored prior to and after exposure to TBQ, using the Chlortetracycline assay. In addition, sperm motility was assessed at each time point and after sperm had been exposed to TBQ. The treatment of sperm with TBQ caused a significant increase in the number of capacitated sperm with an optimum response being achieved in the presence of 100 microM TBQ. However, sperm motility was found not to be effected by the addition of TBQ. The results from the present study suggest that elevating intracellular calcium levels in human sperm by short exposure to a high concentration of TBQ can rapidly accelerate the capacitation process. Furthermore, the observation that TBQ did not elicit a change in sperm motility suggests that TBQ may be highly specific in its mode of action by acting within the head region of human sperm.

The aim of this study was to investigate the effect of an internal calcium ATPase inhibitor, TBQ, on human sperm capacitation and the acrosome reaction during incubation in a calcium-depleted media. Sperm were isolated into and incubated for up to 6 hr in media depleted of Ca2+ and two Ca(2+)-containing media controls. At set time intervals, sperm in each media group were treated with 100 microM TBQ for 5 min. Afterwards, sperm were induced to acrosome react using the divalent cation ionophore, A23187, as a measure of sperm fertilizing potential. It was established, using the Chlortetracycline assay, that incubation of sperm in a Ca(2+)-depleted media inhibited or delayed sperm capacitation resulting in fewer spontaneous or A23187-induced acrosome reacted sperm. However, incubation of sperm in a Ca(2+)-depleted media did not appear to inhibit sperm motility. The treatment of sperm with TBQ during their incubation in Ca(2+)-depleted media was found to have very little effect resulting in low numbers of capacitated and acrosome reacted sperm. The results from this study suggest that human sperm have an obligatory requirement for extracellular calcium during capacitation and the acrosome reaction, but may require either very little extracellular Ca2+ to maintain motility or possess internal Ca2+ stores sufficient for their requirements. In addition, TBQ did not increase the number of capacitated and acrosome reacted sperm during incubation in a Ca(2+)-depleted media suggesting that the TBQ-effect of accelerating sperm capacitation is dependent on presence of extracellular Ca2+.

The purpose of this study was to determine if early adolescence imparts a significant obstetric risk in young primiparas relative to adult primiparas. The records of 239 young primiparas (16 years) and 148 older primiparas (18-29 years) were reviewed for demographic information, antepartum complications, mode of delivery, length of labor, episiotomy, lacerations, birthweight, and length of gestation. The young adolescents were shorter, had an earlier age at menarche, a lower pregravid body mass index, and a higher gestational weight gain. The young teens were less likely to smoke cigarettes but were more likely to be Medicaid recipients. The incidence of most antenatal complications (chronic hypertension, pregnancy-induced hypertension, placental abruption, placenta previa, premature rupture of the membranes, urinary tract infections, and anemia) were similar between the two groups. Preterm labor and contracted pelvis were more common among the young adolescent, while gestational diabetes was less common. The young primiparas were significantly (P.05) less likely to have a Cesarean delivery and to lacerate with vaginal delivery. The length of labor and its stages were similar, as were overall birthweight and length of gestation. Thus, obstetric concerns regarding pregnancy in early adolescence may be unfounded. With the exception of an increased risk for preterm labor, it appears that pregnancy, labor, and delivery do not pose inordinate obstetric and medical risk to the very young adolescent primipara.

Different mitogens elicit similar effects on growth and differentiation of skeletal muscle, suggesting that potential overlap exists in the signaling cascades activated by such factors. To investigate this possibility, we examined the status of STAT and ERK proteins in C2C12 myoblasts and myotubes following stimulation with bFGF or LIF. Both STAT1 and STAT3 as well as ERK1 and ERK2 proteins were detectable in extracts of myoblasts. LIF stimulation of myoblasts lead to rapid phosphorylation on tyrosine of STAT3 and of ERKs 1 and 2. Similarly, bFGF stimulation of myoblasts resulted in the tyrosine phosphorylation of STAT3. However, unlike LIF, the bFGF induced tyrosine phosphorylation of STAT3 appeared cyclical, with recurrent peaks of phosphorylation even after prolonged exposure. By contrast, STAT1 remained unphosphorylated in myoblasts treated with bFGF or LIF. In differentiated myotubes, LIF treatment resulted in the tyrosine phosphorylation of both STAT3 and STAT1, but ERK phosphorylation was not detectable, and bFGF treatment did not lead to STAT1 or STAT3 tyrosine phosphorylation. Therefore these observations suggest that disparate mitogens car activate similar downstream effectors in proliferating myoblasts.

To study the time course of capacitation, spontaneous, and A23187-induced acrosome reaction of human spermatozoa during 8 hours incubation in vitro using the chlortetracycline (CTC) assay with a revised fluorescent pattern classification.Fertile donor spermatozoa were isolated by direct swim-up and incubated in Earle's balanced salt solution for up to 8 hours. At hourly intervals, spermatozoa were stained with CTC before and after the addition of A23187 to induce the acrosome reaction.The University Clinic, Jessop Hospital for Women, Sheffield, United Kingdom.Donors participating in the Donor Insemination Program.Eight fluorescent patterns identified by the CTC assay and acrosome-reacted spermatozoa detected by indirect immunofluorescence using 18.6 monoclonal antibody.Using a statistical model defined by analysis of deviance allowed rationalization of the CTC pattern classification by grouping together patterns that showed a similar and significant change over time. In addition, spontaneous and A23187-induced acrosome-reacted spermatozoa identified by the CTC assay were shown to be correlated significantly to those identified by indirect immunofluorescence.The CTC assay using a revised pattern classification offers a more precise description of human spermatozoa capacitation in vitro. Also, CTC-identified acrosome reaction (both spontaneous and A23187 induced) was confirmed independently by indirect immunofluorescence.

In rats infected with the cestode Taenia taeniaeformis, hepatomegaly results from development of parasitic cysts in the liver. Diffuse nodular mucosal hyperplasia in the glandular region (corpus and antrum) of the stomach, and gross thickening of the intestinal mucosa also result. Between postinfection days (PID) 21 and 84, radiologic observations were made after oral administration of a barium sulfate suspension in T taeniaeformis-infected rats and in age/sex-matched controls. There was radiographic evidence of hepatic enlargement at PID 21. Enlargement of the gastric folds was first observed along the greater curvature of the stomach at PID 35. Fimbriation of small intestinal mucosal surfaces resulted from thickening of the intestinal villi and was observed in the duodenum at PID 21. Intestinal motility was assessed, and contractions were counted, using image intensification fluoroscopy, then were recorded on videotape. There were no significant differences between control and infected rats for gastric emptying time, intestinal transit time, and number of intestinal contractions per minute. Barium contrast radiography clearly indicated large gastric folds, thickening of the small intestinal villi, and hepatic enlargement, and was useful for assessing gastrointestinal motility.

This study presents the first report of the identification of anatomic structures on survey radiographs of the abdomen of the rat, along with detailed barium contrast studies of the gastrointestinal tract in normal rats. The rats (49 to 112 days old) were chemically restrained with a combination of 0.71 mg ketamine hydrochloride/g of body weight and 0.5 mg of acetylpromazine maleate injected intramuscularly. Following sedation, a 36% (wt/vol) micropulverized barium sulfate suspension was administered via a stomach tube at a dose of 0.02 ml/g of body weight. The radiographic features of the gastrointestinal tract were enhanced after coating of the mucosal surfaces with the high-density barium suspension. Internal structures of the stomach and mucosal surfaces of the intestine were clearly identified. The barium contrast study was used to establish gastrointestinal transit times. The mean gastric emptying time was 11 +/- 4.27 (SEM) min and mean intestinal transit time was 5 +/- 0.75 (SEM) h. Image intensification fluoroscopy was used to observe patterns of small intestinal motility and to establish small intestinal contraction rates. Prominent cluster of circular contractions were primarily observed in the jejunum, and wave-type peristalsis was primarily observed in the duodenum. Isolated circular contractions and weak segmentation patterns were observed in the ileum. The mean contraction rate per minute was observed to be 14 +/- 2.12 (SEM) in the jejunum. We propose that under the conditions of the current study, radiographic investigation of gastrointestinal function in rats is a feasible and inexpensive procedure.

To determine the amniotic fluid (AF) volume estimation technique with the greatest diagnostic value with respect to perinatal outcome in the postdate pregnancy.One hundred ninety-eight women who were at least 40 weeks' gestation based on ultrasound confirmation or establishment of dates were evaluated twice weekly with nonstress tests (NSTs) and AF volume estimation. Various indices of AF volume were measured and correlated with perinatal outcome. Receiver operating characteristic curves were used to determine optimal cutoff values.There was a significantly larger maximal vertical pocket in those pregnancies with a normal perinatal outcome than in those with abnormal outcome (4.2 +/- 1.4 versus 3.2 +/- 2.0 cm; P = .02). A statistically significant difference was also seen with the AF index (10.0 +/- 4.5 versus 7.5 +/- 5.0 cm; P = .01). Analysis revealed that the optimal cutoff for identifying clinically significant oligohydramnios was a largest vertical pocket less than 2.7 cm, with an adjusted odds ratio for abnormal perinatal outcome of 7.11 (95% confidence interval [CI] 2.79-18.16). Its sensitivity of 50.0% and specificity of 87.9% were superior to the diagnostic value of the AF index of 5 cm, which had a sensitivity of 29.2% and specificity of 89.1%.A largest vertical pocket threshold of 2.7 cm had the greatest diagnostic value for identifying the postdate pregnancy at risk for abnormal perinatal outcome, surpassing the AF index and the 2-cm largest vertical pocket rule.

Portography is the most commonly used technique for demonstrating portal venous anatomy and abnormal communications between the portal and systemic venous systems. This article reviews normal anatomy, anomalies, and radiology of the portal venous system. Also included is a discussion of cerebral angiography, which is mainly used in the diagnosis of space-occupying lesions of the brain.

Extraosseous chondrosarcomas are uncommon in the dog, and those originating in the lung are rare. This report presents a 9-year-old Beagle dog with a pulmonary mass which caused depression, fever, tachypnea, cough, and laboratory abnormalities. The mass was composed predominantly of chondroid tissue, and was histologically diagnosed as chondrosarcoma.

The myogenic regulatory factors are necessary for the determination and terminal differentiation of skeletal muscle. Gene targeting experiments have demonstrated that MyoD and Myf5 are important for myogenic determination whereas myogenin and MRF4 are important for terminal differentiation and lineage maintenance. During development, all trunk skeletal muscle is derived from the somite. Two spatially distinct sources of myogenic progenitors are defined by the expression of MyoD or Myf5 and these give rise to hypaxial and epaxial musculature. Both in vivo and in vitro analyses have provided a detailed picture regarding the molecular events controlling lineage determination, cell migration, terminal differentiation and tissue repair. Signal transduction pathways regulating cell cycle, protein-protein interactions and myogenic factor gene activation are implicated in the regulation of myogenesis. Recent experiments examining the origin and stem-cell capacity of satellite cells suggest that these cells may originate from the vascular system, are multipotential and may be useful for the treatment of several degenerative diseases.

A model for strong aqueous electrolyte solutions based on fluctuation solution theory is introduced. The key thermodynamic quantities in the model—direct correlation function integrals—are evaluated using results from the mean spherical approximation for mixtures of charged hard spheres for the electrostatic part, from hard sphere mixture theory for the excluded volume part and from corrections for infinite dilution properties obtained from experimental data. This model is compared to experimental data on aqueous NaCl and NaBr solutions at room temperature from infinite dilution to 25% salt by weight at pressures of 1 and 250 bar with very encouraging results.

Quality of prunes is known to be influenced by the temperature and relative humidity of the dehydrator air, and by the time required for drying, long exposures to high temperatures at high humidities resulting in excessive caramelization and cooked taste. To determine the actual temperatures of prunes during dehydration, readings were made by thermocouples inserted at different points in prunes for three test runs at about 166 F, and relative humidities of 15, 27, and 43 per cent. To permit adapting the data obtained to commercial dehydrators, surface thermal conductances were computed. The vapor conductance at the surface was estimated from the thermal conductance, by employing the heat-mass transfer analogy. From the vapor conductance and the evaporation rate, the difference in vapor concentration required to move vapor from the prune surface to the air stream was calculated. Moisture movement within the prune was investigated by cutting the flesh of samples, removed after 3, 6, 10, and 16 hr drying, into two parts, that near the surface, and that near the pit.

The field‐emission projection microscope has been used to study the field‐emission characteristics of several silicon cold cathodes. The current‐voltage data from nine of these field‐emitter tips were reduced to the more fundamental current density ‐ electric field values after the tip geometry was determined in an electron microscope. Comparison of these results with the available theory by Stratton has shown only limited agreement. Two distinct forms have been found for the relationship between the field‐emitted current I and the applied voltage V when plotted as log10 I vs 104/V. One form is ``nonlinear'' while the other is ``linear,'' and the difference between these appears related to the relative strength of a p layer present on the surface of the silicon field‐emitter. A dependence of the field‐emitted current on the temperature of the silicon tip has been observed.

A bag contains m > 0 black balls and n > 0 white balls. A sequence of balls from the bag is discarded in the following manner: (i) A ball is chosen at random and discarded.(ii) Another ball is chosen at random from the remainder. If its colour is different from the last it is replaced in the bag and the process repeated from the beginning (i.e. (i)). If the second ball is the same colour as the first it is discarded and we proceed from (ii). Thus the balls are sampled and discarded until a change in colour occurs, at which point the last ball is replaced and the process starts afresh.

Suppose p and q are two statements. Then, by p implies q, written symbolically as p ⇒ q, we mean that, if p is a true statement then q is also a true statement. Example I Suppose p stands for the statement ‘x is greater than 2’, written a x > 2 for short, and q stands for ‘x > 1’. We write p: x > 2, q: x > 1.

By the end of 1984, as many as one third of all solo practices and two thirds of group practices will have purchased a computer. As many as 25% of these practices, however, will derive only limited benefit from their investment.

The questions of this section are examples of the relationship analysis multiple choice items used in some A-level examinations.

In this chapter we give examples of common mistakes and misconceptions frequently made by students when writing out proofs. In particular, we discuss the examples of chapter 5. However, first we mention some of the more glaring errors and faults which occur far too regularly in examination scripts.

In this chapter we give a number of examples illustrating how a proof should be written out (particularly in the context of examinations). Each example is followed by notes and comment but this is for your benefit and to enable you to understand what has been done. In chapter 6 some of the same examples will be reconsidered and some common errors pointed out.

Among other things, mathematics deals with numbers, symbols, operations, spatial properties and problem solving. Since earliest times the subject has been developed by mathematicians having an intuitive feeling that some proposition is true and then demonstrating the truth, or otherwise, of this proposition by logical argument. When studying mathematics at secondary school, pupils are mainly concerned with learning techniques but, in reality, pure mathematics is mainly concerned with proof. Theorems and proofs did not occur to their originators in the ‘semi-polished’ form which you find in textbooks. The mathematician has an intuitive, instinctive feeling that some proposition may be true. The essence of proof is to establish whether the result is, indeed, true or whether he has been deceived by such a feeling. In this book we discuss various methods of proof which are commonly used in mathematics. Fundamentally, mathematical proof is based on logical argument, that is, to establish from a hypothesis ‘p is true’ a conclusion ‘q is true’.

Before considering some particular techniques of proof, we first make a few general observations which can assist in understanding proofs.