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Conditions for the cold-storage of saffron crocus (Crocus sativus L.) corms to delay flowering have been characterised. Storage of corms at 2℃C after flower initiation resulted in a time-dependent abortion of those flowers already initiated. The more advanced the stage of flower initiation at the beginning of cold-storage, the faster the rate of flower abortion. Overall, no benefit resulted from cold-storing corms after flower initiation. Corms stored in the cold before flower initiation, formed flowers when incubated after storage at 21℃–25℃C. The number and size of flowers formed, and the yield of spice saffron per corm, depended both on the duration and conditions of cold-storage. Storage at freezing temperatures (0℃ or -1℃C) damaged the corms. Flowering could be induced in corms stored between 0.5℃–2℃C. Within this range, temperature had little effect on the subsequent behaviour of corms. Flower number and flower size decreased gradually with increasing duration of cold-storage. This decrease was slower when storage was performed in 1% oxygen than in a normal atmosphere (21% oxygen). Corms lifted after leaf-withering, and stored at 2℃C in 1% oxygen for 70 d, could be forced to flower from early December until the end of January with the same yield of spice saffron as non cold-stored corms. These results complement previous findings on the control of saffron flowering. Taken together, they allow saffron flowering without loss of spice yield from early September to the end of January. Flowering could be further delayed until May by extending the duration of cold-storage, but this delayed flowering resulted in a significant reduction in spice saffron yield. [ABSTRACT FROM AUTHOR]

A seaweed extract (Goemar Spring Cítricos®) from Ascophyllum nodosum was applied to trees of ‘de Nules’ clementine mandarin and Navelina orange at bud sprouting, at full bloom and at the end of the June drop, at a concentration from 0.15% to 0.30%. The seaweed extract increased the yield of ‘de Nules’ clementine mandarin by 11%. The application of 6 mg L-¹ gibberellic acid (GA3) to this cultivar at full bloom increased the yield by 22%, and the combination of seaweed extract and GA3 resulted in a 41% increase of yield. Mean fruit weight was reduced by the GA3-seaweed extract combination, but the amount of marketable fruit was increased. In Navelina orange, seaweed extract at a concentration of 0.15% increased the yield by 8% whereas at a concentration of 0.30% it increased the yield by 15%. No significant differences were observed in the mean fruit weight of this cultivar. [ABSTRACT FROM AUTHOR]

In the Washington navel orange [Citrus sinensis (L.) Osbeck] an increase in the number of flowers results in a reduction of flower weight at anthesis and the initial fruit growth rate, and the number of developing fruitlets increases. Most of these fruitlets are shed during post-anthesis, and the final set of fruit is unrelated to the number of flowers and to the total amount of metabolites and mineral elements used up in fructification but appears to be controlled by the capacity of the tree to supply metabolites to the developing fruitlets during post-anthesis. When the number of flowers is too large, there is a reduction both in the number of initially developing fruitlets and in their growth rate. The final set of fruit is reduced through a different mechanism acting at anthesis and involving differences in mineral composition, which impairs the capacity of the fruit to act as a sink. [ABSTRACT FROM AUTHOR]

The application of gibberellic acid (GA3) at any time from early November until bud sprouting, resulted in a significant inhibition of flowering, in the sweet orange [C. sinensis (L.) Osbeck] and the Satsuma (C. unshiu Marc.) and Clementine (C. reticulata Blanco) mandarins. Two response peaks were evident: the first occurred when the application was timed to the translocation of an unknown flowering signal from the leaves to the buds. The second occurred during bud sprouting, at the time the flower primordia were differentiating. From the pattern of flowering, it appears that the mechanism of inhibition was similar irrespective of the timing of GA3 application. There was an initial reduction in bud sprouting affecting selectively those buds originating leafless inflorescences. An additional inhibition resulted in a reduction in the number of leafy inflorescences with an increase in the number of vegetative shoots, suggesting the reversion of a floral to a vegetative apex. The inhibited buds sprouted readily in vitro but invariably vegetative shoots were formed. A continuous influence of the sustaining branch is necessary to keep the flowering commitment of the buds; irreversible commitment occurs when the petal primordia are well differentiated. [ABSTRACT FROM AUTHOR]

Carbohydrate and mineral nutrition was studied in relation to abscission in fruitlets from leafy inflorescences of the Washington navel orange (Citrus sinensis [L.] Osbeck). Differences in the growth rate of the fruitlets permitted to predict abscission several weeks in advance. This allowed characterization of early differences in composition and behaviour of persisting and abscising fruitlets. Inflorescences with persisting fruitlets accumulated more mineral elements than inflorescences with abscising fruitlets, and for the phloem-mobile elements the excess accumulation was allocated to the fruitlets. Starch accumulated in the inflorescence leaves during early fruitlet growth, and this accumulation was enhanced by the persisting fruitlets despite their higher growth rate and mobilizing ability. The relations between the fruitlets and the inflorescence leaves cannot be explained totally in terms of source sink relationships; a hormonal regulation of the leaves by the fruitlets is postulated. Acid invertase activities and hexose concentration in the pericarp were higher in the abscising fruitlets. The lower early growth rate of these fruitlets is thus not caused by a limitation in carbohydrate supply. It seems more related to carbohydrate utilization, probably hormonally mediated, as demonstrated by the higher dependence on hormone supply for the growth in vitro of the endocarp explants. [ABSTRACT FROM AUTHOR]

The flowering response of Owari Satsuma mandarin (Citrus unshiu Marc) to low temperature treatments has been determined using potted trees and in vitro bud cultures. In potted trees the chilling treatments released bud dormancy and enhanced both sprouting and flowering, but these two responses could not be separated. However, bud cultures showed no dormancy, and a specific effect of low temperature on flower induction was demonstrated. Low temperature appears to have a dual effect, releasing bud dormancy and inducing flowering. Potential flower buds have a deeper dormancy than vegetative buds, and the first stages of flower initiation seem to occur before the winter rest period.

Mineral elements and metabolizable carbohydrates in Citrus leaves [Citrus sinensis (L.) Osbeck cv. Washington navel] have been determined from bud sprouting until the end of the June drop and related to fruitlet growth and abscission. Mineral elements in old leaves decreased during the spring flush of growth and reached minimum values at flower opening, coinciding with a peak in abscission. This was followed by a rapid recovery in potassium and nitrogen to the initial values, with little change afterwards. Old leaves accumulate carbohydrates until flowering, and lose them during post‐anthesis at a constant rate for more than 4 months; this rate of export is unaltered by the presence of a nearby growing fruit. Inflorescence leaves accumulate carbohydrates and mineral elements during post‐anthesis; during the June drop there is an interruption in the accumulation of nitrogen and a net loss of phosphorus, potassium and carbohydrates from these leaves, coinciding with the attainment of the maximum growth rate of the fruit. The two main periods of abscission coincide with minima in the amount of reserves in leaves, suggesting that a limitation in metabolite supply may be the primary cause of drop. There is a closer relationship of the fruit with inflorescence leaves than with old mature ones; however, the regulation of carbohydrate levels in the inflorescence leaves cannot be simply explained in terms of source‐sink relationships with the nearby growing fruit, and the smaller size of inflorescence leaves vs. vegetative ones is not due to the presence of the flower during leaf development. [ABSTRACT FROM AUTHOR]

Natural and post‐harvest ethylene‐induced pigment changes in the rind of Satsuma mandarin (Citrus unshiu Marc.) fruits respond differently to the exogenous application of growth regulators. Both gibberellin A3 and the synthetic cytokinins N6‐benzyladenine and kinetin opposed the ethylene‐induced chlorophyll destruction, while the loss of chlorophyll during natural maturation was retarded by the gibberellin but not by the cytokinins. This different behaviour suggests that ethylene may not be playing a central role in the endogenous control of ripening. Carotenoid accumulation during natural maturation is apparently controlled through a different mechanism than chlorophyll loss since it is reduced both by the cytokinins and gibberellin A3. Kinetin and gibberellin A3 increased to a similar extent the accumulation of reducing sugars and free amino acids, and reduced that of non‐reducing sugars in the peel during natural maturation. Their differential effect on chlorophyll loss may not be explained through their effects on sugar accumulation. [ABSTRACT FROM AUTHOR]

Changes in starch and sugar contents in the cotyledons during germination have been compared in a smooth (cv. Alaska) and a wrinkled (cv. Progress) cultivar of the garden pea (Pisum sativum L.). In both cultivars there was an initial accumulation of sucrose due to the hydrolysis of sucrosyl oligosaccharides, but galactose did not accumulate in the cotyledons. Starch mobilization in the Progress pea was linear with time and started before the rise in α‐amylase (EC 3.2.1.1) activity in the cotyledons; sucrose was synthesized in the cotyledons, and their excision from the axis resulted in an additional accumulation of this sugar. In the Alaska pea, the onset of starch hydrolysis coincided with the rise in α‐amylase activity; no accumulation of sucrose was found in excised cotyledons, whilst the sucrose content decreased continuously in attached cotyledons. The same sugars were found in the cotyledons of both cultivars, suggesting a common pathway for starch breakdown. Maltose, maltotriose and linear malto‐dextrins were not present and only trace amounts of glucose were detected, suggesting a degradation of starch by phosphorylase after an initial attack by α‐amylase. α‐Amylase activity in the cotyledons was higher in the presence of the axis, but was influenced by the water content of the cotyledons. Transient changes in α‐amylase activity correlated well with changes in the rate of starch hydrolysis, but after 2–3 days starch mobilization was reduced in excised cotyledons probably due to the resynthesis of starch. [ABSTRACT FROM AUTHOR]

In the Satsuma mandarin (Citrus unshiu Marc.) the presence of the fruit results in a gradual inhibition of flowering and of bud sprouting. This inhibitory effect starts several months before the onset of the winter rest period and lasts until the end of the accumulation of carotenoids in the fruit peel, more than one month after the completion of fruit growth. During all this time and until natural bud sprouting, flowering and bud sprouting are inhibited by exogenous gibberellic acid. Peak responses to this growth regulator coincide with periods of maximal rates of flowering inhibition by the fruit. Kinetin and abscisic acid, applied at the time of peak response to gibberellic acid, inhibited flowering and reduced the number of shoots developed through the reduction of the number of shoots formed per sprouted node, but failed to reduce the number of nodes which sprouted. The same pattern of sprouting was obtained in trees treated with gibberellic acid during the winter rest period or several months earlier. It is concluded that some step leading to flowering and which determines the differences in sensitivity of the buds to this growth regulator has taken place already at this early date. [ABSTRACT FROM AUTHOR]

Surface electroenterogram (EEnG) is a non-invasive method to study bowel myoelectrical activity. Nevertheless, surface recorded EEnG is contaminated by respiratory, motion artifacts, and other interferences. The goal of this paper is to remove the respiration artifact and ultra-low frequency components from surface EEnG by means of empirical mode decomposition (EMD). Seven recording sessions on abdominal surface of three Beagle dogs were conducted. Power percentages of interferences and of fundamental slow wave were calculated before and after the application of the method. The results show that the interference power is significantly reduced (23 +/- 16% vs. 5 +/- 4%), and fundamental slow wave power is significantly increased (59 +/- 17% vs. 76 +/- 13%). Therefore, the EMD method can be helpful to remove respiration and ultra-low frequency components from the external EEnG recordings.

This study is based on a review of the present situation of tetanus neonatorum. This study included 34 cases which were diagnosed as tetanus of the newborn. These 34 cases occurred in Dr A. Pumarejo hospital in the city of H. Matamoros, Tamaulipas (Mexico), during the period 1970-1974. It was found that during this pediatric age, in comparison with others, the incidence is high (61.8%) and shows a predominance of males over females of 4.62 to 1. The incidence of this pathology, as Cole & Youngman proposed, was as follows: grade I, 2.94% grade II, 11.76%; and 85.30% corresponding to grade III. The greater number of deaths were in those patients classified as grade III, which corresponded to 12 patients. The number of cases studied during spring and summer was much higher. The living conditions within our environment, our ecology and the unawareness of the basic means to prevent this pathology (correct management of the umbilical cord) were the main causes of this high incidence. Therefore, this case study leads to the conclusion that there is a great need to reorganize our programs of vaccination in order to protect this pediatric group, which is highly exposed.