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Eotetranychus lewisi (McGregor) is an important pest mite found in peach crops. This pest has recently been reported in the province of Tungurahua, Ecuador, little information is available. The biology and life table of E. lewisi using three peach cultivars (Zapallo, Blanco Abridor, and Tejón) was evaluated under laboratory conditions (19°C, 45% R.H., and 12:12 L.D). Mites were collected from Euphorbia pulcherrima growing at the Faculty of Agricultural Sciences, Technical University of Ambato. The mites were able to grow through the immature phase of the Blanco Abridor and Tejón cultivars. The mean duration of the immature phase (egg to adult) did not show significant differences between the Blanco Abridor and Tejón cultivars, ranging from 16.24 to 16.56 days. The mean female fecundity reared on Tejón was 18% higher than on Blanco Abridor, though their longevity was similar on both. The mean net reproductive rate (R0) was higher on Tejón (61.25), suggesting that more females will be born when the mites are raised on this cultivar. Based on our results, Tejón and Blanco Abridor were susceptible to E. lewisi; while, the mites could not reach adulthood on Zapallo, suggesting at least some resistance mechanisms, however more detailed studies are required. [ABSTRACT FROM AUTHOR]

The concept of biointerface emerges in the fields of biochemistry, genomics, cellular biology and life science. The integration of nanoparticles and biointerfaces creates the scope in different areas like biology, biochemistry, biotechnology and microbiology. The mode of action of nanoparticles through biointerface involves the formation of the protein corona, cellular contact, endocytosis and intracellular transport. The article highlights the complexation of host-guest and types of biointerfaces based on the principles of light, pH, redox reaction and competitive binding. Three major theories include Arrhenius theory, interfacial theory and electron theory. Apart from electron transfer, polymer complexation and kinetic drug release, the energy of activation play an important role in the formation of biointerface. The applications of nano-biointerface include cell patterning, gene delivery, blood-contacting device and cancer therapy. The review article focuses on the potential of biointerface in nano-based systems due to longer contact time, higher surface area, better drug loading efficiency and adhesion for increasing lift-off force, cell penetration, drug delivery of nanocarriers and on-targeting effect to the infected cells. Further, advancement in this field will increase the efficiency of gaseous systems like nanobubbles, nanodroplets, nanoshells, nanocages and nanopopcorn. [ABSTRACT FROM AUTHOR]

Scientific research seems to proceed in terms of the assumption that the universe is lawful and if fully understood would reveal a unity. We do not expect nor is it the case that a finding in one area of knowledge is unrelated to or contradicts a finding or principle in another. The more we learn the more it appears that the findings from biology fit into those from chemistry, for example, and so with other areas of research.... The examples could go on and on, but they all point, in my experience, to one conclusion: the more one knows, the more it seems that all things fit into a great whole. [ABSTRACT FROM AUTHOR]

The article offers discussion on the biosphere, industriosphere and their interaction. The biosphere is the thin, discontinuous mantle of life which surrounds the earth and includes natural ecosystems, agricultural ecosystems and man while the industriosphere which is located within, and supported by the biosphere is the series of fossil-fuel powered patches of human industrial activity. To maintain their respective systems and produce goods and services useful to man, both the biosphere and industriosphere use energy, principally derive from the sun to rearrange the chemicals of the Earth's crust. However, the uncontrolled growth and development of industriosphere has degraded human existence through pollution and industrial squalor and threatened the productivity of the biosphere.

The article discusses the plight of science education. According to the author, it appears feasible to organize and direct science education into the one essential goal that is being neglected: that of self-preservation. The chief concern of nature is reproduction, and must it must be made a primary objective among scientists. Reproduction takes place at every level of instruction, and only through instruction. Science education should also be directed toward effective communication that will reach the public and impart a knowledge of science, its aims, its methods, its achievements, to every segment of a nation that has risen to greatness through science and the applications of science.

The article presents a discussion of the role of the scientist in relation to environmental problems. The problems of the environment are found at the interface between the biosphere and the technosphere. Some of the duties of a natural scientist include undertaking research oriented towards the improvement of the human environment, acting as a scientist in public environmental issues, maintaining and renewing the ethics of scientific research, and contributing to the development of a new social ethics.

Reproduction is a part of life cycle with great environmental dependence. In contrast to temperate avian species, which mostly breed during summer, the Indian songbirds have more flexible breeding programs and exhibit a spectrum of reproductive strategies with the breeding season scattered all over the year. Control of breeding cycles in the Indian songbirds, therefore, are broadly viewed in light of two strategies (i) birds showing strong photoperiodic component in regulation of reproductive and post-reproductive events (ii) birds that do not exhibit typical photoperiodic regulation indicating the involvement of an inherent rhythm of reproduction. Both circadian and circannual rhythms have been demonstrated to regulate annual gonadal cycles of Indian songbirds. While photoperiod continues to be a predominant proximate factor for timing of breeding in majority of Indian songbirds investigated so far, some studies reveal the role of non photoperiodic cues such as the food availability, temperature, rainfall, etc. in timing/modulating the timing of breeding. The conversion or non-conversion of thyroxine to triiodothyronine may act as a long or short photoperiod signal and may up or downregulate the synthesis and release of GnRH-I in hypothalamus, FSH and LH in anterior pituitary and gonadal steroids in gonads causing gonadal growth or regression, respectively. [ABSTRACT FROM AUTHOR]

The unique organism project was designed as a culminating assessment for a biological classification unit in a middle school setting. Students developed a model to represent their unique organism. Using the model, students were required to demonstrate how their unique organism interacts with its environment, and how its internal and external structure and organization allowed it to carry out those interactions. The NGSS Cross Cutting Concepts of structure and function, systems, and system models along with the Science & Engineering Practice of constructing models were integrated and emphasized throughout the unit. [ABSTRACT FROM AUTHOR]

The article presents a discussion on the progress in biology, and reflects on how these developments can become a cause of confusion and apprehension by affecting established equilibria, destroying certain prejudices, and confronting human conscience with unexpected and difficult problems. The discussion focuses on the inevitable consequences of the natural evolution of biology. These developments in biology include the prolongation of life, voluntary determination of sex, and the virginal procreation.

Twenty broad bean,Vicia fabaL., stocks were evaluated under clay field conditions, pH 8.1, located at the Western Experimental Station of the Faculty of Agriculture, Cairo University, Giza for their relative susceptibility against the stunt nematode,Tylenchorhynchus latusand other tylenchids. Statistical differences (p ⩽ 0.05 and 0.01) in the studied stocks are found in either final nematode populations or the plant growth and yield components. The potential of each stock to support build-up of the stunt nematode or other tylenchids was estimated in relation to that of L 99 stock or L 348, respectively, which were regarded as check stocks and the host category based on the potential reproduction index of each cultivar was estimated. In this respect, the studied stocks could be categorised for their susceptibility againstT. latusas follow: L 241 stock only was rated as resistant to the nematode. L 31 stock was observed to be less susceptible. Twelve stocks of broad bean out of twenty were graded as moderately susceptible. On the other hand, only six broad bean stocks namely L 99, G 429, L 92, L 24, L 13 and L 46 were categorised as highly susceptible (HS). It is worth noticed that reproduction of nematode was favoured on HS and susceptible cultivars but suppressed on resistant one. So, all evaluated stocks showed great variability in their reaction to the nematode infection based on the host type. Also, various plant growth and yield components of broad bean stocks were also discussed. Eventually, the differences among the tested cultivars should serve as a good resource for plant breeders and cropping systems to limit the loss due to the nematode infection. [ABSTRACT FROM PUBLISHER]

A multi-strain model of a vector-borne disease with distributed delay in the vector and the host is investigated. It is shown that if the reproduction number of the model ℛ0<1, the unique disease-free equilibrium is globally asymptotically stable. Without loss of generality, strain one is assumed to have the largest reproduction number. In this case, the dominance equilibrium of strain one is shown to be locally stable. The basic reproduction number for a straini() is written as a product of the reproduction number of the vectorand the reproduction number of the host, i.e.. The competitive exclusion principle is derived under the somewhat stronger condition that if strain one maximizes both the reproduction number of the hostand the reproduction number of the vector, strain one dominance equilibrium is globally asymptotically stable. [ABSTRACT FROM PUBLISHER]

Two new species are here described and illustrated:Falkovitshella hindukushisp. nov. from north-eastern Afghanistan, andScythris wadiqeltellasp. nov. from Palestine.Scythris inconspicuellaSinev is newly recorded from China, markedly extending its known range.http://www.zoobank,org/urn:lsid:zoobank.org:pub:2BC5092F-D004-4CB3-85C7-1CAA54AAE536 [ABSTRACT FROM AUTHOR]

The aim of this multicentre, prospective, randomised, investigator blind, controlled clinical trial was to evaluate the clinical efficacy and tolerability of a highly purified human menopausal gonadotrophin (hMG) preparation (Merional-HG) when administered to patients undergoing controlled ovarian stimulation (COS) for in-vitro fertilisation (IVF) procedure enrolled in hospital departments. One hundred fifty-seven patients were randomised in two parallel groups: 78 started COS with Merional-HG and 79 with Menopur. Results of the study showed that both highly purified hMG preparations were equivalent in terms of number of oocytes retrieved (primary endpoint: 8.8 ± 3.9 versus 8.4 ± 3.8, p = 0.54). In the patients treated with Merional-HG, we observed a higher occurrence of mature oocytes (78.3% versus 71.4%, p = 0.005) and a reduced quantity of gonadotrophins administered per cycle (2.556 ± 636 IU versus 2.969 ± 855 IU, p < 0.001). Fertilisation, cleavage, implantation rates and the number of positive β-human chorionic gonadotrophin (hCG; pregnancy) tests and the clinical pregnancy rate were comparable in the two groups. Both treatments were well tolerated. In conclusion, the results of this study support the efficacy and safety of Merional-HG administered subcutaneously for assisted reproduction techniques. Efficiency of Merional-HG appears to be higher due to reduced quantity of drug used and the higher yield of mature oocytes retrieved. [ABSTRACT FROM AUTHOR]

The article focuses on the research initiative Asian Biopoleis: Practice, Place and Life at the National University of Singapore (NUS) since 2010. It is noted that the NUS project represents the first comprehensive social science and humanities research collaboration, funded by a national granting agency that is dedicated to bioscience and biomedicine in Asia.

This article is an inquiry into how analysts and psychotherapists can respond to the environmental crisis within the context of the analytic process. It addresses a perspective on individual and cultural defenses that separate us from a relational context within the matrix of life. A view is presented that regards humans as integral with the natural world, emphasizing the wild nature of psyche, embodiment, and the analytic process as a way of learning to engage this wildness. Building on Thomas Berry's idea that hope for our future lies in our human participation in the dream of the earth, case vignettes introduce the truth telling of the imaginal, proposing that we listen for how dreaming unfolds within one's self, between one's self and another, and between ourselves and the earth. [ABSTRACT FROM AUTHOR]

Portunid crabs are an important resource in estuaries, and require appropriate management to guarantee their long-term availability. We investigated the population dynamics and reproduction of Callinectes danae in the Estuarine–Bay Complex of São Vicente, São Paulo, Brazil, to provide basic biological information for public policies for the management of this fishery. Monthly samples were obtained from March 2007 to February 2008 on eight transects, four in the estuary and four in the bay. A total of 2261 specimens (403 males, 1288 females, of which 570 were ovigerous) were collected. Males were significantly larger than females, and the size–frequency distribution was unimodal for males, females and ovigerous females. The sex ratio was nearly always skewed toward females (M:F - 1:4.6). C. danae showed seasonal-continuous reproduction, with high reproductive activity in the warmer season. C. danae breeds in the estuarine–bay complex, with males and juvenile females concentrated in the estuary. After copulation, fertilized females migrate to the estuary entrance and the bay, where ovigerous females are commonly found spawning in high-salinity areas. Therefore, to manage this important economic resource, both the estuary and the bay should be considered for protection, but special attention should be given to the estuary entrance during the summer months, when ovigerous females concentrate. [ABSTRACT FROM AUTHOR]

The article focuses on synthetic biology which refers to a collection of techniques and agendas to define and construct basic living systems from minimal sets of molecules. It mentions that synthetic biology can potentially contribute to science, medicines and preservation of nature if the principles are implemented in reversible ways with appropriate safety monitoring and controls. It concludes that the lack of proper oversight and risk assessment hinders the pursuance of the application.

Relational biology is a study of life in terms of the organization of entailment relations in living systems, independent of any particular physical mechanism or material realization. Anticipatory systems and metabolism–repair (M,R)-systems are two classes of relational models that characterize life. In this paper, I explore the connections between them: I explicate the circumstances under which anticipation occurs in an (M,R)-system, and show that the entailment pattern of an anticipatory system may be represented as a network of metabolism and repair components. [ABSTRACT FROM PUBLISHER]

We studied the biology of the ambrosia beetle Platypus quercivorus in the logs of five tree species to determine: (1) the relationship between the amount of frass produced by beetles and tunnel length, (2) the relationship between frass shape and the morphological characteristics of P. quercivorus mouthparts, and (3) the suitability of five tree species for P. quercivorus reproduction. Five logs each from healthy Quercus crispula, Q. serrata, Castanea crenata, Sorbus japonica, and Cryptomeria japonica trees were used in this experiment. The results showed that there was a linear relationship between the amount of frass and tunnel length. Whenever powdery frass was produced, larvae were found in the gallery in the log, while fibrous frass was present only in galleries that contained just adults. The mouthparts of adults were completely sclerotized, which likely accounts for the fibrous frass production. Host preference of P. quercivorus was examined at two stages using five tree species. The first stage is digging initiation, which concerns male preference for digging a tunnel. More holes were made by males on S. japonica and Q. serrata logs, while fewer holes were made on C. japonica logs. The second stage is characterized by female orientation, mating, and progeny development. Platypus quercivorus could complete its lifecycle only in the two Quercus spp. [ABSTRACT FROM AUTHOR]

The striped sea bream, Lithognathus mormyrus, used for this population dynamics study were obtained from longline catches and market sampling in the Algarve (south Portugal). The macroscopic analysis of the gonads and the gonad somatic index showed that the south Portuguese population of L. mormyrus spawns mainly between late spring and summer (June to August). The length at first maturity was similar for males and females and the value for both sexes combined was estimated to be 16.08 cm, corresponding to an age between 1 and 2 years. Fish age classes (0 to 13) were determined by reading growth rings on whole otoliths. Age determination was validated by marginal increment analysis. The estimated parameters of the von Bertalanffy growth equation were L∞=35.30 cm, K=0.264 and t 0= - 0.809. Mortality rates were calculated for fish captured with longlines, and the estimated parameters were M=0.356, Z=0.622 and F=0.266. From an Algarve fishery management perspective, these results suggest the need for an increase in the minimum landing size (from 15 to 17 cm), which should be beneficial for the sustainability and conservation of this species. The results also showed that fishing with longlines off the Algarve coast may allow for a sustainable use of the resource. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including the baby's experience of time at the beginning of life, the experience of time by a transgendered patient at birth, and the past.

Studies on the reproduction, longevity and life table parameters of Typhlodromus athiasae Porath and Swirski and Amblyseius cabonus Schicha and El Shafie were carried out under laboratory conditions of 25 ± 1°C and 75 ± 5% RH. As food sources for both phytoseiid mites, nymphs of the spider mite Tetranychus urticae Koch (Acari: Tetranychidae) and the motile stages of the eriophyid mite Eriophes dioscoridis Soliman and Abou Awad (Acari: Eriophyidae) were selected. Both diets were accepted as food by females of T. athiasae, while no development beyond the protonymphal stage occurred in the case of A. cabonus. For T. athiasae, the developmental periods was similar on both diets, while the adult longevity was shorter (28.7 days compared to 36.3 days) and reproduction was higher (61.5 eggs/female compared to 49.6 eggs/female), when fed on E. dioscoridis compared with T. urticae as food. A higher value of net reproduction rate (Ro = 45.51), intrinsic rate of increase (rm = 0.2884), finite rate of increase (λ = 1.33) and shorter mean generation time (T = 13.23 days) were recorded when T. athiasae was offered E. dioscoridis as food. The number of eggs deposited per day by T. athiasae was higher (2.8 eggs/female/day) on E. dioscoridis than on T. urticae (2.0 eggs/female/day). [ABSTRACT FROM AUTHOR]

The rice brown planthopper, Nilaparvata lugens (Stål) (Homoptera: Delphacidae), is the type of insect pest whose resurgence is induced by pesticides. Outbreaks of the pest frequently occur in Asia. We investigated the effects of series of concentrations of four insecticides, imidacloprid, buprofezin, deltamethrin and triazophos, on the durations of the preoviposition (DPP) and oviposition period (DOP), female longevity (LOF), realized fecundity (RFE) and egg hatchability of N. lugens on two rice varieties: TN1 and Xieyou 963. DPP, DOP, LOF, NLE and hatchability varied with insecticide type, concentration, number of applications, and rice variety. For imidacloprid and buprofezin, RFE and hatchability decreased, DPP increased, and DOP and LOF lessened significantly with increasing concentration. In contrast, for deltamethrin and triazophos, DPP and DOP shortened, and LOF, RFE and hatchability increased significantly with increasing concentration. Increase in the number of applications for the four insecticides amplified the effects on these life-history variables. For example, three successive sprays of deltamethrin significantly increased RFE compared to a single spray under the same concentrations and rice variety. Additionally, rice variety also showed a significant influence on the variables. For example, RFE on TN1 significantly increased compared to on Xieyou 963 under the same concentrations and spray times. There were significant correlations between each index and insecticide concentrations for four insecticides on both rice varieties except in the case of hatchability for a single spray of buprofezin on TN1 and for LOF for a single spray of deltamethrin on TN1. Our findings have important implications for the understanding of mechanisms of N. lugens resurgence, and for management of the pest in commercial rice production. [ABSTRACT FROM AUTHOR]

Gamma radiation was tested as a means of increasing production of the egg parasitoid Trichogramma chilonis Ishii by improving the suitability of host eggs and by stimulating reproduction of the parasitoid females. For manipulation of the host eggs' suitability, radiation was used to either (a) produce developmentally-inactivated (DI) eggs incapable of hatching, or (b) to produce F1 sterile host eggs. For treatment of the parasitoid females with the intent of stimulating reproduction, parasitoid pupae were exposed to very low dose radiation (250 mGray). For tests on host suitability using radiation-induced DI host eggs, newly-laid (<8 h old) host eggs (Helicoverpa armigera Hubner) were exposed to 300 Gy of 60Co gamma radiation. For tests of F1 sterile host eggs, H. armigera moths were mated with individuals exposed to 250 Gy as pupae. Tests were performed with eggs resulting from all possibilities of normal (N) and sterile (S) ♀ × ♂ matings. Both types of DI host eggs (irradiated or sterile), along with untreated host eggs (controls), were exposed to T. chilonis females, using the following host egg-to-parasitoid ratios: 1:10, 1:30, 1:60 and 1:90. Developmentally-inactivated host eggs exposed to 300 Gy did not differ in suitability from normal host eggs at a 1:10 parasitoid-host ratio, but were significantly more suitable at the higher host-parasitoid ratios. F1 sterile eggs were not significantly different in suitability from normal eggs at a 1:10 host-parasitoid ratio but were marginally better at the higher host-parasitoid ratios. In tests performed using T. chilonis females exposed to low-dose radiation (250 mGy), no effects were observed when cohorts of 5 T. chilonis females were provided with only 50 host eggs, but when more hosts were provided (ratios of 1:30, 1:60 and 1:90), significantly higher rates of parasitization were noted for the parasitoids exposed to low-dose radiation. This effect prevailed using both normal host eggs and DI host eggs exposed to 300 Gy. The stimulatory effect also was noted when F1 sterile host eggs were provided to the irradiated T. chilonis females. These results suggest that release of T. chilonis irradiated with 250 mGy may complement release of irradiated H. armigera moths, which produce sterile F1 eggs that can serve as supplemental hosts in the field and thereby enhance the pest management system. [ABSTRACT FROM AUTHOR]

Some small populations are characterized by periods of exponential growth interrupted by sudden drops. These drops can be linked to the population size itself, for example, through overexploitation of local resources. The long-term population extinction risk and the time to extinction for such a repeatedly collapsing population are estimated from general branching processes. The latter allows realistic modeling of lifespan distributions and reproduction patterns, litter (or brood or clutch) sizes as long as individuals reproduce freely and density effects are absent. As the population grows, the carrying capacity of the habitat increasingly matters. This is modeled as a drop after reaching a ceiling. The probability of recovery is then determined by the population size after the drop and by the risk of extinction of branching processes. The reproductive behavior of individuals during the periods free of density effects determines the intrinsic rate of increase of populations close to the carrying capacity. The details of life history which produce demographic stochasticity remain important in systems with density effects. Finally, the time to extinction of a single system with a high carrying capacity is compared to that of a population distributed over several small patches. For systems not allowing migration, survival is favored by a single large habitat rather than by several small habitats. [ABSTRACT FROM AUTHOR]

Eight geographic populations of Brachionus ca1yc~florus collected from China were cultured at 18°C, 23°C, and 28°C with 3.0x106cells/mL of alga Scenedesmus obliquus to investigate their asexual and sexual reproduction. There were significant effects of both temperature and geographic population, independently and in interaction on population growth rate, fertilization rate of mictic females, and resting egg production of the rotifers. Geographic population and interaction between temperature and geographic population influenced significantly mixis rate in the rotifer population. [ABSTRACT FROM AUTHOR]

Limnomedusa is a monotypic genus that occurs in association with rocky outcrops and stream beds. Based on observational and mark-recapture fieldwork from 2005 to 2008, we report the breeding biology of Limnomedusa macroglossa in southern Brazil. The reproductive season lasted from late August to early February. Tadpoles were recorded from early September to late February. A clear pattern of emergence/recruitment was observed in juveniles. The occurrence of reproductive activities was clearly related to the longest photoperiods, when the highest temperatures occur. Males called from rocky or concrete substrates, mostly under rocks. Amplexus was axillary and the operational sex ratio was nearly even. Spawn occurred in lentic water bodies but tadpoles also completed their development in slow-flowing water. Although using similar habitats for reproduction, L. macroglossa reached lower levels of specialization toward terrestriality than did the cycloramphids Cycloramphus and Thoropa. We classify L. macroglossa as a breeding habitat specialist that would be threatened by river damming. [ABSTRACT FROM AUTHOR]

The aim of this paper is to examine the statistical relevance of bird species on the endpoints of avian long-term toxicity studies (eggs laid, eggs set, eggs hatching, embryo survivor, 14-day old survivors and eggshell thickness). Data from 561 animals of three different species (Colinus virginianus, Anas platyrynchos and Coturnix coturnix japonica) tested with five different pesticides were analyzed in this study. The substances considered were: Thiamethoxam (EZ-3-(2-chloro-1,3-thiazol-5-ylmethyl)-5-methyl-1,3,5-oxadiazinan-4-ylidene(nitro)amine), Thiacloprid ((Z)-3-(6-chloro-3-pyridylmethyl)-1,3-thiazolidin-2-ylidenecyanamide), Acetamiprid ((E)-N1-[(6-chloro-3-pyridyl)methyl]-N2-cyano-N1-methylacetamidine), Phosmet (O,O-dimethyl S-phthalimidomethyl phosphorodithioate) and Dicofol (2,2,2-trichloro-1,1-bis(4-chlorophenyl)ethanol). Several general lineal mixed models were conducted to evaluate the factors affecting variables used in long-term reproductive toxicity tests. Test significance was p < 0.01 in all models tested. Model R2 value was high (0.80) for all variables except for eggs laid (R2 = 0.42) for the three species studied. Tukey studentized range test showed significant differences among species and pesticides. For pre-hatching period the differences were significant for eggs laid and eggs set among species. C. japonica showed statistical differences for egg hatching. With respect to embryo survivor and 14 days old survival, significant different were found for C.virginianus and A. platyrynchos, respectively. These results indicate that the selected species have an influence in the endpoints to be used for risk assessment. [ABSTRACT FROM AUTHOR]

The author presents an analysis on the effect of sentinel lymphadenectomy to patient's survival. He argues that survival benefit from the treatment of lymph nodes is imparted by early removal of nodal metastases. The author advices that it is important that lymph nodes which first affected by infective protoplasm be remove, and bar entrance into the blood.

This article examines how Paracelsus understands seeds in his notion of corporeality in his early works. In his article, "Invisible Wombs: Rethinking Paracelsus's Concept of Body and Matter" (Ambix 53.2), Dane Thor Daniel classified the Archiodoxen of 1527 as Paracelsus's early work. My essay argues that Archiodoxen demonstrates a development in Paracelsus's thinking, and suggests how Buch von der Gebärung (ca. 1520) and Volumen Paramirum (ca. 1520) represent Paracelsus's human seed theory in its earliest stages. In these works, Paracelsus does not necessarily base his seed theory entirely on scripture, but rather focuses on the relationship between nature and the human seed. [ABSTRACT FROM AUTHOR]

The enigmatic deuterostome Xenoturbella does ubiquitously contain exogenous nucleic acids. This has been used in several papers as proof of selective feeding by Xenoturbella on nuculid bivalves. However, their feeding biology is unknown and exogenous nucleic acids might not originate from their main nutrient source. I have examined the possible pathways of nutrient uptake. The animals neither took up cells nor dissolved dyes through the 'mouth'. Instead, they possessed extensive pinocytosis through the epidermis. Therefore, it is probable that the main source of nutrients is dissolved organic matter uptaken through the epidermis. This does not exclude that phagocytosis in the gastrodermis does occur, e.g. due to direct expose of the gastrodermis during asexual reproduction. The ubiquitously present exogenous nucleic acids in Xenoturbella probably do originate from such events and not from their main food source. [ABSTRACT FROM AUTHOR]

The present study compares the ability of conventional condition indices (based on weight of the whole organism, weight of its flesh, and/or its shell weight) and visual quantitative indices (based on measures of the digestive gland, gonad, and capsule gland on digitized images of sections of these organs) for the assessment of reproductive activity in Hexaplex trunculus. To estimate conventional indices, a total of 120 standard-sized specimens (50 males and 70 females) in the 60-70 mm shell length interval were analysed. To estimate visual quantitative indices, a total of 903 specimens (501 males and 402 females) were analysed for the gonadosomatic index (GSI); females were also analysed for the capsule gland index (CGI). Compared to conventional indices, the visual quantitative indices (GSI and CGI) followed seasonal variations of the species reproductive cycle and identified broad changes in reproductive development (being highly accurate in detecting the main period of gonad maturation and spawning that occurred between May and June). Results indicate that both GSI and CGI constitute simple, practical and efficient indices for the routine assessment of reproductive activity in H. trunculus, providing a useful and reliable alternative to conventional condition indices and to histological analyses. Results of this study encourage the use of similar sampling procedures and analytical techniques, and analogous visual quantitative indices, to assess reproductive activity in other gastropod species. [ABSTRACT FROM AUTHOR]

The herbicide atrazine is widely used in agriculture for the production of corn and other crops. Because of its physical and chemical properties, atrazine is found in small concentrations in surface waters—habitats for some species. A number of reports on the effects of atrazine on aquatic vertebrates, mostly amphibians, have been published, yet there is inconsistency in the effects reported, and inconsistency between studies in different laboratories. We have brought the results and conclusions of all of the relevant laboratory and field studies together in this critical review and assessed causality using procedures for the identification of causative agents of disease and ecoepidemiology derived from Koch's postulates and the Bradford-Hill guidelines. Based on a weight of evidence analysis of all of the data, the central theory that environmentally relevant concentrations of atrazine affect reproduction and/or reproductive development in fish, amphibians, and reptiles is not supported by the vast majority of observations. The same conclusions also hold for the supporting theories such as induction of aromatase, the enzyme that converts testosterone to estradiol. For other responses, such as immune function, stress endocrinology, parasitism, or population-level effects, there are no indications of effects or there is such a paucity of good data that definitive conclusions cannot be made. [ABSTRACT FROM AUTHOR]

Results from 13 additional host populations improves resolution on the diversity of Wolbachia bacteria in Spalangia spp. (Hymenoptera: Pteromalidae). These bacteria are of interest because they can profoundly affect their host's reproduction. Manipulating Wolbachia infections may provide a method to improve the efficacy of biocontrol agents including Spalangia spp. [ABSTRACT FROM AUTHOR]

As part of a long-term moose browse/fire severity study, we used the Normalized Burn Ratio (NBR) with historic Landsat Thematic Mapper (TM) imagery to estimate fire severity from a 1983 wildfire in interior Alaska. Fire severity was estimated in the field by measuring the depth of the organic soil at 57 sites during the summer of 2006. Sites were selected for field sampling from five fire severity classes based on threshold NBR values. The linear relationship between post-fire NBR and organic soil depth among sites within the burn was weak (r 2 = 0.26), and improved substantially (r 2 = 0.66) when restricted to non-wetland black spruce sites. The relationship between NBR and aspen/willow counts was non-linear. Sites with high densities of aspen stems consistently occurred in the high fire severity classes, and sites with high willow stem densities consistently occurred in the moderate fire severity class. However, NBR varied substantially from sites with low aspen or willow reproduction and therefore predicting aspen or willow regeneration based on post-fire NBR values would be difficult. [ABSTRACT FROM AUTHOR]

Four 1 km global land cover products are currently available to the scientific community: the University of Maryland (UMD) global land cover product, the International Geosphere-Biosphere Programme Data and Information System Cover (IGBP-DISCover), the MODerate resolution Imaging Spectrometer (MODIS) global land cover product and Global Land Cover 2000 (GLC2000). Because of differences in data sources, temporal scales, classification systems and methodologies, it is important to compare and validate these global maps before using them for a variety of studies at regional to global scales. This study aimed to perform the validation and comparison of the four global land cover datasets, and to examine the suitability and accuracy of different coarse spatial resolution datasets in mapping and monitoring cropland across China. To meet this objective, we compared the four global land cover products with the National Land Cover Dataset 2000 (NLCD-2000) at three scales to evaluate the accuracy of estimates of aggregated cropland areas in China. This was followed by a spatial comparison to assess the accuracies of the four products in estimating the spatial distribution of cropland across China. A comparative analysis showed that there are varying levels of apparent discrepancies in estimating the cropland of China between these four global land cover datasets, and that both area totals and spatial (dis)agreement between them vary from region to region. Among these, the MODIS dataset has the best fit in depicting China's croplands. The coarse spatial resolution and the per pixel classification approach, as well as landscape heterogeneity, are the main reasons for the large discrepancies between the global land cover datasets tested and the reference data. [ABSTRACT FROM AUTHOR]

The important role of hybridity in the evolution of the genus Gagea is becoming clear, through morphological, karyological and molecular evidences. Several species were recently inferred or hypothesized to be of hybrid origin; especially in sect. Didymobulbos, sect. Fistulosae and sect. Gagea. Representative case studies, such as G. luberonensis J.-M. Tison, G. polidorii J.-M. Tison and G. pomeranica Ruthe, are presented and discussed. Since many Gagea species show very reduced or null sexual reproduction vs. a massive vegetative propagation, there are several problems in distinguishing hybrids from hybridogenous species in this genus. The actual trend is to consider them at specific level because of their ability to stabilize, at least through vegetative propagation by bulblets and/or bulbils. [ABSTRACT FROM AUTHOR]

We present here the known life history, ecology, and distribution of the Jackson Lake springsnail (Pyrgulopsis robusta) based on original research, field collected information, and review of the available literature from primary sources, government publications, and private industry reports. We report on the feeding, reproductive biology, life cycle, habitat use, and distribution of P. robusta in the northwestern United States. [ABSTRACT FROM AUTHOR]

We examined the fine structure of gametes and the auxospore wall in the heterothallic pennate raphid diatom Nitzschia longissima (sensu Karsten 1897). The presence of scales in the gamete wall of both sexes is demonstrated for the first time for a pennate diatom species. Silica in scales was documented by energy dispersive x-ray spectroscopy. This finding supports our earlier hypothesis that scales are present in pennate sex cells more often than previously considered and reflect their evolutionary relationship to scale-bearing ancestors. In addition, the auxospore was shown to contain both transverse and longitudinal perizonia as well as longitudinal bands with fimbriate margins. Longitudinal bands are also novel components of a pennate auxospore. All these structures are either difficult to resolve or irresolvable in light microscopy (LM), clearly demonstrating that LM is not sufficient to investigate diatom sex cell structure. The sexual process employed by N. longissima is compared to its congenerics. Unlike other species from this genus, our diatom is morphologically and behaviourally anisogamous. In addition, the copulation of gametangia is not aided by copulation tubes, papillae or copulation jellies. Therefore, sexual reproduction in N. longissima shows little similarity to that of the few other species in the genus Nitzschia thus far examined. [ABSTRACT FROM AUTHOR]

In contrast to numerous studies showing breeding seasonality for animals living in temperate zones, few have addressed the effect of annual environmental changes on hormones and behavior related to reproduction for animals living in tropical and equatorial regions. In order to expand information on other primates living near the equator, we used 13 adult common marmosets, eight males and five females living under natural climatic conditions in a colony located in North-Eastern Brazil. Blood samples were collected monthly from July 2002 to June 2004. Cortisol assays were performed by ELISA. Cortisol levels varied according to environmental temperature and rainfall but were not significantly affected by photoperiod. After separating out these environmental effects through an analysis of covariance for repeated measurements, a marginal significant difference in cortisol levels according to the seasons of the year was detected. A significant difference in cortisol levels between females and males was also observed. The results suggest that annual variation in cortisol in common marmosets is influenced by temperature and rainfall and might be associated with the mating season. [ABSTRACT FROM AUTHOR]

We consider a three-stage discrete-time population model with density-dependent survivorship and time-dependent reproduction. We provide stability analysis for two types of birth mechanisms: continuous and seasonal. We show that when birth is continuous there exists a unique globally stable interior equilibrium provided that the inherent net reproductive number is greater than unity. If it is less than unity, then extinction is the population's fate. We then analyze the case when birth is a function of period two and show that the unique two-cycle is globally attracting when the inherent net reproductive number is greater than unity, while if it is less than unity the population goes to extinction. The two birth types are then compared. It is shown that for low birth rates the adult average number over a one-year period is always higher when reproduction is continuous. Numerical simulations suggest that this remains true for high birth rates. Thus periodic birth rates of period two are deleterious for the three-stage population model. This is different from the results obtained for a two-stage model discussed by Ackleh and Jang (J. Diff. Equ. Appl., 13, 261-274, 2007), where it was shown that for low birth rates seasonal breeding results in higher adult averages. [ABSTRACT FROM AUTHOR]

We studied diet composition and overlap of the exotic noodlefish (Neosalanx taihuensis) and the endemic fish Anabarilius grahami in a deep, oligotrophic lake in the Yurman Plateau. d. grahami dominated the fish community in Lake Fuxian before the invasion of N. taihuensis in 1982, but it is now in the process of extinction, corresponding with an explosive increase in N. taihuensis population. Schoener's index (α = 0.773) indicate that N. taihuensis and A. grahami have significant diet overlap, with both fish feeding mainly on zooplankton. An increased proportion of littoral prey, such as Procladius spp., Coleoptera, and epiphytes, in the diet of A. grahami indicated that this endemic fish shifted its main habitat from the off-shore zone in the late 1980s to the littoral zone at the present. A difference in reproduction between the two fishes, along with the overfishing, may have exacerbated the occupation of A. grahami's pelagic niche by N. taihuensis. The endemic species has shown large competitive disadvantage for food and space in the presence of N. taihuensis. [ABSTRACT FROM AUTHOR]

The article investigates the adaptive strategies of Polysiphonia adamsiae and P. strictissima living in conditions subject to sand deposition and amphipod grazing using in situ field observations and experimental culture in southern New Zealand. The study showed that branches regenerated from prostate axes and fragments for both species grew 7 to 10 times faster than sporelings under the same culture conditions. It is also indicated that vegetative modes of reproduction predominated over sporic modes in both species, which might be advantageous for thalli to survive amphipod grazing under turf-tapped sand.

Plants are essential to life on Earth and yet are often deemed invisible by the human populace. Botanic gardens are an under-researched educational context and, as such, have occupied a peripheral arena in biology education discussions. This article seeks to readdress this absence and present the case for a more sustained use of informal learning environments, such as botanic gardens and homes, to make public the private life of plants and their role in sustaining life on Earth. By drawing on empirical data from a doctoral thesis and reviewing relevant research literature, the author argues for a renewed focus on botanical education within science education in both formal and informal contexts. [ABSTRACT FROM AUTHOR]

The aim of this article is to use the episode of the baby allegedly cloned by the Raelians and born on the day after Christmas 2002 in order to analyse what is threatened by the prospect of cloning as a reproductive method, and why it is a matter of such importance as to provoke immediate and general condemnation. The announcement made by the Raelians provoked public debate in the media. Therefore, analysis of the articles published in the main Italian newspapers during that period allows exploration of the hypothesis that the Raelians' attempt of cloning was generally interpreted as a threat against the basis of our conception of human identity, not only at the individual level - which defines each of us as a balance between difference and continuity - but also at the social level, where human identity is the result of a classification system in which human beings are identified in contrast to other living beings. For these reasons, the case of the Raelians is of particular interest because it strains the reproduction/identity nexus in an extreme way which highlights what otherwise may lie buried beneath a thick layer of taken-for-granted beliefs. [ABSTRACT FROM AUTHOR]

Community-based ecosystem management requires understanding a community's capacity. We argue that communities can make important contributions not only to specific assessments of community capacity, but also to the conceptualization of the term itself through community-based research methods that are both adaptive and reflexive. A research initiative that illustrates such practices is reported here. We begin by describing our initial conceptual framework of community capacity that identified resource capitals and mobilizing factors. In focus groups, residents of two Canadian biosphere reserves used this framework to assess their capacity to meet biosphere reserve mandates and to provide critical reflections that helped to drive revisions to the framework. Our new framework is more sensitive to temporal and spatial dimensions of capacity, local social relations, and local culture. We conclude that adaptive and reflexive community-based offer methodological alternatives for research, help advance conceptions of community capacity, and help produce social change. [ABSTRACT FROM AUTHOR]

The main purpose of this research was to evaluate the use of anthropometric activities among a sample of 761 high-school biology students in terms of student outcomes (achievement and attitudes) and classroom environment (assessed with the Science Laboratory Environment Inventory, SLEI). Data analyses supported the SLEI's factorial validity, internal consistency reliability and ability to differentiate between classrooms. The efficacy of using anthropometric activities was supported by pretest-posttest differences in achievement, as well as by a comparison with a control group's attitudes and perceptions of classroom learning environment. Overall, results provide a degree of support for the positive influence of using anthropometric activities in terms of students' attitudes and the classroom learning environment. [ABSTRACT FROM AUTHOR]

Exponential models are very popular for the assessment of clinical research. Nature is unpredictable and exponential models may be adequate for simple organisms but less so for human beings. Theobjective was to review the potential advantages and limitations of this approach. The following models were reviewed: Cox proportional hazard regression, Markow modeling, polynomial regression for Laplace transformed multi-exponential models, and logistic regression. Real and hypothesized data were used as examples. In conclusion, the advantages include: the possibility to conveniently study subgroup effects, otherwise called confounders; the possibility to derive pharmacokinetic parameters; andthe possibility to make long-term predictions from observational data. Limitations include: the exponential models may not fit the data well enough; they may give rise to some serious misinterpretations of the data; most of the statistical software for exponential models assumes that confounders are homogeneous, while, in reality, this is virtually never true; and the exponential models are a major simplification for the description of research data in human beings. We underline that exponential modeling, although a very interesting tool for exploratory research, is not adequately reliable for confirmational research. It is to be hoped that this paper will help investigators to more cautiously interpret the results of their exponential data analysis. [ABSTRACT FROM AUTHOR]

The Harold B. Lee Library at Brigham Young University (BYU) recently implemented a number of information literacy strategies to help students in Biology 100, a large general education class, find. resources for their term assignment. The library's services for Biology 100 students were evaluated using focus groups composed of both teaching assistants and students. This paper will describe the class and the assignment, discuss the impact the class had on library staff, detail the efforts of the staff to meet the needs of Biology 100 students, and present results of focus groups used to evaluate the library's outreach and teaching efforts. [ABSTRACT FROM AUTHOR]