Changes in photosynthesis,growth, and sugar content of commercial sugarcane cultivars and Erianthus under flood conditions

Sugarcane (Saccharum spp.) is an economical crop in the tropical and subtropical countries. However, because of global climate change, flooding has become problematic, particularly during the rainy season, in Thailand. We investigated the effects of floods on three commercial sugarcane cultivars, namely NiF8, U-thong 6 (UT6), and U-thong 9 (UT9), as well as Erianthus spp. Growth was assessed using a pot experiment in a glasshouse with two treatments: (1) control and (2) 60 d of flooding followed by 30 d of normal conditions. In comparison with control, during prolonged flooding, Erianthus showed greatly decreased CO₂ assimilation, whereas NiF8, UT6, and UT9 showed slightly declined CO₂ assimilation. Growth in plants subjected to 60 d of flooding was less influenced by floods while sucrose content was not affected except in UT6. During flooding, some roots died, resulting in plants compensating adventitious roots to offset the negative effects of root death and to assist them in maintaining their growth, which appeared from the submerged nodes, with different characteristics for each cultivar. However, 30 d after draining, roots remained damaged, while adventitious roots died, resulting in lesser growth as compared with the control, but it did not significantly affect sucrose content and sugar yield. This study suggests that sugarcane plants need to produce the adventitious roots to compensate their roots’ death during flooding and require time to recover their root system after flooding for obtaining the optimum yield and quality at harvest.     

电泳引入CB-HRP在鸡端脑内的有效扩散范围的研究

将CB－HRP经电泳引入火鸡左侧古纹状体，动物分别存活2h、5h、12h、17．5h、24h、48h，灌杀。做脑干和大脑半球的冰冻连续切片，TMB成色，中性红复染，光镜下明、晴视野对照观察。结果发现：1．CB－HRP被引入古纹状体后，其酶液扩散范围于2h最大直径为1．689mm；5h达到2.675mm;8h亦达2.675mm，12h时为2．253mm；17．5h时为1．830mm；24h时为0.845mm;48h时为0.422mm.2．CB－HRP被引入12h时在耳蜗居核、顶盖灰质及三叉神经感觉主核出现小范围的顺行标记给本，及至48h时脑干内出现广泛的颁行标记物。经测算其顺行运输速率可达96mm／d。     

A novel method for estimating the adaptive ability of guide dogs using salivary sIgA

Salivary secretory immunoglobulin A (sIgA) concentrations of prospective guide dogs for the blind were determined to clarify whether salivary sIgA is useful in evaluating the potential suitability of guide dogs for the blind. Saliva was collected from 73 prospective guide dogs in the kennel on day 1 (the day of separation from volunteer puppy-raisers), 2, 3, 7 and 14 during the estimation period (at about 1 year old). We selected particularly suitable dogs (superior dogs) and unsuitable dogs (inferior dogs) on the basis of the trainers' estimation. All dogs were divided into two groups, those were acceptable dogs would become the guide dogs and rejected dogs could not become guide dogs. The sIgA concentrations in superior dogs gradually increased from day 1 to 14 and those in inferior dogs remained at low levels. Moreover, the sIgA concentrations on day 14 in the acceptable dogs were significantly higher than those in rejected dogs. The cut-off point of sIgA concentrations on day 14 using an ROC curve was 90 EU/ml, and the specificity of the estimation at this point (70.4%) was higher than that of trainers' estimation (50%). Moreover, parallel testing using both trainers' estimation and sIgA estimation, showed that specificity was further improved (79.5%). The present study showed that sIgA concentration was extremely useful in estimating the adaptive ability for guide dogs for the blind.     

Preimplantation development of embryos in labrador retrievers

Preimplantation development of canine embryos is not well understood. To understand the timing of preattachment embryogenesis relative to the luteinizing hormone (LH) surge, early embryonic development was examined in Labrador Retrievers after artificial insemination. The embryos migrated from the oviduct to the uterus beginning on day 11 after the LH surge. This transport must be completed within 24 h. By day 13 after the LH surge, all of the embryos had moved and were localized in the uterus. The embryos developed to the morula stage within 11-13 days and to the blastocyst stage within 14 days after the LH surge, respectively. These findings add to the current understanding concerning the physiology of preimplantation development and should help further develop assisted reproductive techniques in canine species, such as cryopreservation and subsequent embryo transfer.     

Distribution and stem growth patterns of mangrove species along the Nakara River in Iriomote Island, Southwestern Japan

We examined variations in stand structure and tree growth of a mangrove forest along two gradients: from the river mouth to upper stream and from the riverside to inland, along the Nakara River, Iriomote Island, Japan. Bruguiera gymnorrhiza (L.) Lamk. occurred throughout the intertidal area, though Rhizophora stylosa Griff. and Kandelia candel (L) Druce did not occur upstream. Basal area and maximum tree height of B. gymnorrhiza decreased downstream. The growth rate in stem diameter of B. gymnorrhiza decreased downstream in relation with the soil salinity. The basal area and the maximum tree height of B. gymnorrhiza increased with the distance from the riverside. R. stylosa increased in stem diameter and growth rate toward the riverside.     

Artificial insemination with canine spermatozoa frozen in a skim milk/glucose-based extender

Due to the recent outbreak of avian influenza, transportation of frozen canine semen with egg yolk has been sharply restricted. Thus, there is urgent need to develop a novel egg yolk-free extender for freezing canine spermatozoa. In the present study, the effect of using skim milk/glucose (SG)-based extender without egg yolk on the motility and fertilizing capacity of canine spermatozoa frozen-thawed in the presence of glycerol was examined. There was a tendency for the proportion of motile spermatozoa exposed to SG-based extender for 3 h to be higher than that exposed for 1 h, but the difference was not significant. The motility and other viability parameters of canine spermatozoa after thawing were similar to those obtained with an egg yolk-based extender. When spermatozoa frozen with SG-based extender containing glycerol after 3 h exposure were transcervically inseminated into 2 recipient bitches, a total of 6 pups were obtained. These results suggest that a simple extender composed of skim milk, glucose and glycerol is useful for cryopreservation of canine spermatozoa, which may contribute to improved exchange of genetic material and efficient production of companion and working dogs, such as guide dogs for the blind.     

Australopithecus garhi: a new species of early hominid from Ethiopia

The lack of an adequate hominid fossil record in eastern Africa between 2 and 3 million years ago (Ma) has hampered investigations of early hominid phylogeny. Discovery of 2.5 Ma hominid cranial and dental remains from the Hata beds of Ethiopia's Middle Awash allows recognition of a new species of Australopithecus. This species is descended from Australopithecus afarensis and is a candidate ancestor for early Homo. Contemporary postcranial remains feature a derived humanlike humeral/femoral ratio and an apelike upper arm-to-lower arm ratio.     

Cities and biodiversity: Perspectives and governance challenges for implementing the convention on biological diversity (CBD) at the city level

City governments are fundamental to implement international environmental agreements, such as the convention on biological diversity (CBD). Even though many of them are not directly involved in the negotiation of international agreements, which are signed by national governments, most of those agreements are in fact implemented at the city level. The importance of city governance to tackle the challenges of biodiversity loss has increased as urban population has grown enormously in the last decades, particularly in developing countries. The way cities are designed, planned and governed influences the magnitude of their direct and indirect impacts on biodiversity.This paper analyzes the relationship between cities, local governance and biodiversity. Initially, we examine the relationships between cities and biodiversity by looking at the major influences cities have on biodiversity loss or conservation within and outside the city boundaries, as well as the benefits of biodiversity conservation to cities, such as the provision of ecosystem services. The paper then moves to understand what are the main urban processes and governance mechanisms that can be improved to make cities effective to implement the directives of the CBD.Urbanization creates new challenges for biodiversity conservation. As a large part of the world’s population moves from rural to urban areas, there are changes in the link between human activities and biodiversity, and consequently to the way we should think biodiversity conservation policies. However, scarce attention has been given to understand how to make cities more biodiversity friendly, both within the urban fabric, but particularly in faraway places.     

Effects of duration and combination of drought and flood conditions on leaf photosynthesis,growth and sugar content in sugarcane

Global climate change will result in extreme environments, such as droughts and floods. We investigated the individual and combined effects of droughts and floods of varying duration on sugarcane (Saccharum spp.) growth using a pot experiment under glasshouse conditions with the following six treatments: drought for 15 d, prolonged drought for 30 d, flood for 15 d, prolonged flood for 30 d, short flood followed by prolonged drought, and prolonged flood followed by prolonged drought. Plants that were subjected to drought conditions, including drought after a flood, had reduced CO₂ assimilation (through stomatal closure) and leaf areas, whereas flood conditions showed no effect. During flooding, some roots died, and adventitious roots with well-developed aerenchyma appeared from the submerged nodes. At the time of harvest, there were no significant differences in stem fresh weight, sucrose content, or sugar yield between the treatments. However, ion content analysis revealed that flood conditions caused an accumulation of sodium in the bottom of stems and adventitious roots. Therefore, under flood conditions, plants may develop adventitious roots, which may offset the negative effects of root death, helping them to maintain their growth and yield.     

Cryopreservation of canine ovaries by vitrification

The cryopreservation of ovarian tissues is a technology with significant potential for the preservation of the genetic resource materials of working dogs, including guide dogs for the blind. However, no attempt has been reported on cryopreservation of the canine ovary. Thus, we evaluated a vitrification method for cryopreservation of canine ovaries and determined the potential functionality of vitrified-warmed canine ovaries by means of transplantation into non-obese diabetic-severe combined immunodeficiency (NOD-SCID) mice. All ovarian tissues cryopreserved by vitrification were morphologically normal in terms of histology. Cryopreserved ovaries were transplanted into the ovarian bursa of the NOD-SCID mice, and the xenografts were recovered from 23 of 23 mice (100%) 4 weeks after the operation. The transplanted canine tissue was tightly adhered to the mouse ovary. Although antral follicle formation did not occur after grafting, proliferating cell nuclear antigen immunoreactivity was detectable in many of the granulosa cells in the primary follicles of the grafts. These results indicate that cryopreservation of the canine ovary by vitrification appears to have the potential to restore endocrine function and ovulation potential.