Current status of farming practices of striped catfish, Pangasianodon hypophthalmus in the Mekong Delta, Vietnam

Aquaculture of catfish, Pangasianodon hypophthalmus (Sauvage), locally known as “ca tra”, and commonly referred to as striped catfish, river catfish and sutchi catfish, in Vietnam, having recorded a production of 683,000 tonnes in 2007, valued at about 645 million US$ is one of the largest single species based farming system, restricted to a small geographical area, in the world. The product is almost totally exported to over 100 countries as frozen fillets, as an acceptable alternative to white fish. Catfish is farmed mostly in earthen ponds, up to 4 m deep, in nine provinces in the Mekong Delta in South Vietnam. The results of the grow-out system of catfish farming in the Mekong Delta from a survey of 89 farms are presented. The farm size ranged from 0.2 to 30 ha with a mean of 4.09 ha. The frequency distribution of the yield in tonne/ha/crop and tonne/ML/crop corresponded to a normal distribution curve, where 75% of the farms yielded 300 tonnes/ha/crop or more. It was found that the yield per crop was significantly correlated (p < 0.05) to stocking density, pond depth and volume but not to pond surface area. Yields per crop was significantly different (p < 0.05) between upper and lower provinces of the Mekong Delta and water source (river versus channels), amongst others. It was evident that diseases and/or symptoms were observed to occur mostly in accordance with the onset of rains. In this paper the history of the catfish farming in the Mekong Delta is briefly traced, and current harvesting and marketing procedures as well as pertinent social elements of the farming community are dealt with.

Presbyterian ethos and environment in the novels of John Buchan : a religious and historical study

The aim of this thesis is to establish, from a historical and religious perspective, that the Presbyterian ethos and environment in which John Buchan was reared was the predominating influence in the writing of his novels. Presbyterianism was not the only influence on Buchan that determined the character of his stories. Buchan was by temperament a romantic, and this had considerable influence on his literature. His novels are romances, peopled by romantic figures who pursue romantic adventures. There are the signs of Buchan's romantic nature in the contents of the novels: creative imagination, sensitivity to nature, and expectations of the intrusion of other worlds, with destiny-determining events to follow. But Buchan had also an acquired classicism. His studies at Glasgow and Oxford Universities brought him in touch with a whole range of the master-pieces of classical literature, especially the works of Plato and Virgil. This discipline gave him clarity and conciseness in style, and balanced the romantic element in him, keeping his work within the bounds of reason. At the heart of Buchan's life and work, however, was his deeply religious nature and this, while influenced by romanticism and classicism, was the dominant force behind his work. Buchan did not accept in its entirety the Presbyterian doctrine conveyed to him by his father and his Church. He was moderate by temperament and shrank from excesses in religious matters, and, being a romantic, he shied away from any fixed creeds. He did embrace the fundamentals of Christianity, however, which he learned from his father and his Church, even if he did put aside the Rev. John's orthodox Calvinism. The basic Christianity which underlies all Buchan's novels has the stamp of Presbyterianism upon it, and that stamp is evident in his characters and their adventures. The expression of Christianity which Buchan embraced was the Christian Platonism of seventeenth century theologians, who taught and preached at Cambridge University, They gave prominence to the place of reason and conscience in man's search for God, They believed that reason and conscience were the ‘candle of the Lord’ which was existed every one. It was their conviction that, if that light was followed, it would lead men and women to God. They were against superstition and fanaticism in religion, against all forms of persecution for religious beliefs, and insisted that God could only be known by renouncing evil and setting oneself to live according to God’s will. This teaching Buchan received, but the stamp of his Presbyterianism was not obliterated. The basic doctrines which arose from his father's Presbyterianism and are to be found in Buchan's novels are as follows: a. the fear (or awe) of God, as life's basic religious attitude; b. the Providence of God as the ultimate determinative force in the outcome of events; c. the reality, malignity and universality of evil which must be forcefully and constantly resisted; d. the dignity of human beings in bearing God's image; e. the conviction that life has meaning and that its ultimate goal, therefore, is a spiritual one - as opposed to the accumulation of wealth, the achieving of recognition from society, and the gaining access to power; f. the necessity of challenge in life for growth and fulfilment, and the importance of fortitude in successfully meeting such challenge; g. the belief that, in the purpose of God, the weak confound the strong. These emphases of Presbyterianism are to be found in all Buchan's novels, to a greater or lesser degree. All his characters are serious people, with a moral purpose in life. Like the pilgrims of the Bible, they seek a country: true fulfilment. This quest becomes more spiritual and more dearly defined as Buchan grows in age and maturity. The progress is to be traced from his early novels, where fulfilment is sought in honour and self-approving competence, as advocated by classicism; to the novels of his middle years, where fulfilment is sought in adventures suggested by romanticism. In his final novel Sick Heart River. Buchan appears to have moved somewhat from his earlier classicism and his romanticism as the road to fulfilment. In this novel, Buchan expresses what, for him, is ultimate fulfilment: a conversion to God that produces self-sacrificing love for others. The terminally-ill Edward Leithen sets out on a romantic adventure that will enable him to die with dignity, and so, in classic style, justify his existence. He has a belief in God, but in a God who is almighty, distant and largely irrelevant to Leithen's life. In the frozen North of Canada, where he expects to find his meagre beliefs in God's absolute power confirmed by the icy majesty of mountain and plain, he finds instead God's mercy and it melts his heart. In a Christ-like way, he brings life to others through his death, believing that, through death, he will find life. There is sufficient evidence to give plausibility to the view that Buchan is describing in Leithen his own pilgrimage. If so, it means that Buchan found his way back to the fundamental experience of the Christian life, conversion, so strongly emphasised in his orthodox Presbyterianism home and Church. However, Buchan reaches this conclusion in a Christian Platonist way, through the natural world, rather than through the more orthodox pathway of Scripture.

Changes in the composition of the extracellular matrix in patellar tendinopathy

Objective: To compare the chemical levels and mRNA expression of proteoglycan and collagen in normal human patellar tendons and tendons exhibiting chronic overuse tendinopathy.

Methods: Sulfated glycosaminoglycan and hydroxyproline content were investigated by spectrophotometric measurement using papain-digested samples. Deglycosylated proteoglycan core proteins were analysed by Western blot using specific antibodies. Total mRNA isolated from samples of frozen tendons was assayed by relative quantitative RT-PCR for decorin, biglycan, fibromodulin, versican, aggrecan, and collagens Type I, II and III and normalised to glyceraldehyde-3-phosphate dehydrogenase.

Results: There was a significant increase in sulfated glycosaminoglycan content in pathologic tendons compared to normal. This was attributed to an increased deposition of the large aggregating proteoglycans versican and aggrecan and the small proteoglycans biglycan and fibromodulin, but not decorin. Aggrecan and versican were extensively degraded in both normal and pathologic tendons, biglycan was more fragmented in the pathologic tendons while predominantly intact fibromodulin and decorin were present in normal and pathologic tendons. There was a greater range in total collagen content but no change in the level of total collagen in pathologic tendons. There were no significant differences between the pathologic and normal tendon for all genes, however p values close to 0.05 indicated a trend in downregulation of Type I collagen and fibromodulin, and upregulation in versican and Type III genes in pathologic tissue.

Conclusion: The changes in proteoglycan and collagen levels observed in patellar tendinopathy appear to be primarily due to changes in the metabolic turnover of these macromolecules. Changes in the expression of these macromolecules may not play a major role in this process.

Pulse-lavage brushing followed by hydrogen peroxide-gauze packing for bone-bed preparation in cemented total hip arthroplasty : a bovine model

To compare the effectiveness of pulse-lavage brushing followed by hydrogen peroxide-gauze packing with either technique alone or normal-saline irrigation in bone-bed preparation for cemented total hip arthroplasty. 44 fresh-frozen ox femoral canals were prepared for cemented total hip arthroplasty using 4 techniques: normal-saline irrigation, pulse-lavage brushing, hydrogen peroxide-soaked gauze packing, and a combination of the latter 2 techniques. The maximum tensile pull-out force required to separate the prosthesis from the femoral canal was measured as an indicator of the strength of the cement-bone interface. The mean pull-out force to separate the prosthesis from the femoral canal was significantly higher in specimens prepared with pulse-lavage brushing followed by hydrogen peroxide-soaked gauze packing or pulse-lavage brushing alone than those prepared with normal-saline irrigation or hydrogen peroxide-soaked gauze packing alone 300(p<0.001). Pulse-lavage brushing is more effective at cleansing the femoral canal and increasing mechanical strength at the cement-bone interface than preparation with normal-saline irrigation or hydrogen peroxide-soaked gauze packing.

Epizootiology of brucella infection in Australian fur seals

Novel members of the bacterial genus Brucella have recently emerged as pathogens of various marine mammal species and as potential zoonotic agents. We investigated the epizootiology of Brucella infection in Australian fur seals (Arctocephalus pusillus doriferus) by establishing demographic and temporal variations in antibody prevalence, attempting isolation of the causative agent, and determining whether this potential pathogen is involved in frequent abortions observed in this pinniped species. Two competitive enzyme-linked immunosorbent assays (cELISAs), an indirect ELISA, and a fluorescence polarization assay (FPA) were used to test sera for Brucella antibodies. The FPA and cELISA proved suitable for use in this species. Significant differences in antibody prevalence were found between age classes of seals sampled between 2007 and 2009 at one colony. Pups sampled at this site (n5134) were negative for Brucella antibodies by all serologic tests but 17 of 45 (38%) of juveniles were antibody-positive. Antibody prevalence in adult females was significantly higher than in juveniles (P50.044). Antibody prevalence for adult females between 2003 and 2009 varied significantly over time (P50.011), and for individuals sampled between 2003 and 2005, the likelihood of pregnancy was greater in individuals positive for Brucella antibodies (P50.034). Inflammatory lesions suggestive of infectious agents were found in 14 of 39 aborted Australian fur seal pups, but pathologic changes were not uniformly consistent for Brucella infection. Culture and PCR investigations on fetal tissues were negative for Brucella. Culture and PCR on selected fresh or frozen tissues from 36 juvenile and adult animals were also negative. We suspect that the prevalence of active infection with Brucella in Australian fur seals is low relative to antibody prevalence. © Wildlife Disease Association 2011.

cGMP phosphodiesterase inhibition improves the vascular and metabolic actions of insulin in skeletal muscle

There is considerable support for the concept that insulin-mediated increases in microvascular blood flow to muscle impact significantly on muscle glucose uptake. Since the microvascular blood flow increases with insulin have been shown to be nitric oxide-dependent inhibition of cGMP-degrading phosphodiesterases (cGMP PDEs) is predicted to enhance insulin-mediated increases in microvascular perfusion and muscle glucose uptake. Therefore, we studied the effects of the pan-cGMP PDE inhibitor zaprinast on the metabolic and vascular actions of insulin in muscle. Hyperinsulinemic euglycemic clamps (3 mU·min−1·kg−1) were performed in anesthetized rats and changes in microvascular blood flow assessed from rates of 1-methylxanthine metabolism across the muscle bed by capillary xanthine oxidase in response to insulin and zaprinast. We also characterized cGMP PDE isoform expression in muscle by real-time PCR and immunostaining of frozen muscle sections. Zaprinast enhanced insulin-mediated microvascular perfusion by 29% and muscle glucose uptake by 89%, while whole body glucose infusion rate during insulin infusion was increased by 33% at 2 h. PDE2, -9, and -10 were the major isoforms expressed at the mRNA level in muscle, while PDE1B, -9A, -10A, and -11A proteins were expressed in blood vessels. Acute administration of the cGMP PDE inhibitor zaprinast enhances muscle microvascular blood flow and glucose uptake response to insulin. The expression of a number of cGMP PDE isoforms in skeletal muscle suggests that targeting specific cGMP PDE isoforms may provide a promising avenue for development of a novel class of therapeutics for enhancing muscle insulin sensitivity.

Development of microfluidic-based analytical methodology for studying the effects of chemotherapy agents on cancer tissue

Whilst a multitude of techniques have been employed to study the biology of tumour tissue and its response to chemotherapeutic reagents, most current methodologies do not capture the sophistication of the in vivo environment. Microfluidics however offers the ability to maintain and interrogate primary tissue samples in an environment with biomimetic flow characteristics. In this study head and neck squamous cell carcinoma (HNSCC) tumour biopsies have been used to investigate the performance of a microfluidic device for generating clinically-useful information. The response of fresh and cryogenically-frozen primary HNSCC or metastatic lymph node samples to chemotherapy drugs (cisplatin, 5-flurouracil or docetaxel), alone and in combination, were monitored for both proliferation (water-soluble tetrazolium salt metabolism) and cell death biomarker release (lactate dehydrogenase, LDH) “off-chip”. The frozen tissue showed no significant difference in terms of either proliferation or LDH release in comparison with the matched fresh samples. Administration of all drugs caused cell death, in a dose-response manner, with the combination showing the greatest amount of cytotoxicity particularly at days 8 and 9; correlating well with published clinical data. The system described here offers an innovative method for studying the tumour microenvironment in vitro and, through incorporation of relevant analytical modules, provides the basis of a pre-clinical device that can be used to define personalised treatment regimens.

A five-gene hedgehog signature developed as a patient preselection tool for hedgehog inhibitor therapy in medulloblastoma

Purpose: 

Influence of price discounts and skill-building strategies on purchase and consumption of healthy food and beverages: outcomes of the Supermarket Healthy Eating for Life randomized controlled trial

BACKGROUND: Fiscal strategies are increasingly considered upstream nutrition promotion measures. However, few trials have investigated the effectiveness or cost effectiveness of pricing manipulations on diet in real-world settings. OBJECTIVE: We assessed the effects on fruit, vegetable, and beverage purchasing and consumption of a 20% price-reduction intervention, a tailored skills-based behavior-change intervention, and a combined intervention compared with a control condition. DESIGN: The Supermarket Healthy Eating for Life trial was a randomized controlled trial conducted over 3 mo [baseline (time 1) to postintervention (time 2) with a 6-mo follow-up (time 3)]. Female primary household shoppers in Melbourne, Australia, were randomly assigned to a 1) skill-building (n = 160), 2) price-reduction (n = 161), 3) combined skill-building and price-reduction (n = 160), or 4) control (n = 161) group. Supermarket transaction data and surveys were used to measure the following study outcomes: fruit, vegetable, and beverage purchases and self-reported fruit and vegetable consumption at each time point. RESULTS: At 3 mo (time 2), price reduction-alone participants purchased more total vegetables and frozen vegetables than did controls. Price reduction-alone and price reduction-plus-skill-building participants purchased more fruit than did controls. Relative to controls, in the price-reduction group, total vegetable consumption increased by 233 g/wk (3.1 servings or 15% more than at baseline), and fruit purchases increased by 364 g/wk (2.4 servings; 35% more than at baseline). Increases were not maintained 6 mo postintervention (time 3). Price reduction-alone participants showed a tendency for a slight increase in fruit consumption at time 2 (P = 0.09) that was maintained at time 3 (P = 0.014). No intervention improved purchases of bottled water or low-calorie beverages. CONCLUSIONS: A 20% price reduction in fruit and vegetables resulted in increased purchasing per household of 35% for fruit and 15% for vegetables over the price-reduction period. These findings show that price modifications can directly increase produce purchases. The Supermarket Healthy Eating for Life trial was registered at Current Controlled Trials Registration as ISRCTN39432901.

Spatial design 3.0

Spatial Design 3.0 forms a new dialogue between the artist and design artefacts, lens-based practice and the entanglements of contemporary critical theory. The artist was invited to exhibit at the Peninsula Art Gallery in Plymouth, UK at the Envelop Exhibition as part of the UK Festival of Design 2015. The artwork involves wire, photography, printing, mark making, typography and patterns negotiated and frozen within spatial arrangements. These elements are manipulated as a means to engage the traditional tools and instruments of art and design methodology in contemporary practice. The work was published and internationally distributed in the accompanying catalogue.

Long-distance endozoochorous dispersal of submerged macrophyte seeds by migratory waterbirds in northern Europe - a critical review of possibilities and limitations

We review whether migratory Anatidae, i.e., swans, geese and ducks, could be acting as vectors for dispersal of Zostera, Ruppia and Potamogeton propagules by endozoochory (carrying seeds in their guts). We list six prerequisites that must all be fulfilled, if successful dispersal should occur. Several Anatidae species feed on these macrophytes, and undertake rapid long-distance movements, making dispersal possible. We identify four problems, which in combination leads us to conclude that long-distance dispersal events are likely to be rare. (i) Most long-distance movements are out of phase with the reproductive efforts of the plants, and if birds arrive at sites when plants still bear seeds, they are likely to depart well after seed stocks have been depleted. (ii) Seed transport by birds will usually be uni-directional, from north to south on autumn migrations. (iii) Most of the gut contents of migratory birds are likely to have been discarded within 300 km of departure. (iv) In many cases, birds will arrive in habitats seriously different from those they departed, i.e., any seeds carried along will have low chances of surviving in their new site. We suggest that northbound dispersal by endozoochory can only occur during spring if waterbirds feed on seeds that have not been depleted and remained frozen down or buried in sediments, or during moult- or post-moult migrations. Moult migration takes place in summer in phase with the reproductive efforts of the plants. Also epizoochorous dispersal (external attachment) is subject to restrictions i, ii and iv.

Wingbeat frequency and the body drag anomaly: wind-tunnel observations on a thrush nightingale (Luscinia Luscinia) and a teal (Anas crecca)

A teal (Anas crecca) and a thrush nightingale (Luscinia luscinia) were trained to fly in the Lund wind tunnel for periods of up to 3 and 16 h respectively. Both birds flew in steady flapping flight, with such regularity that their wingbeat frequencies could be determined by viewing them through a shutter stroboscope. When flying at a constant air speed, the teal's wingbeat frequency varied with the 0.364 power of the body mass and the thrush nightingale's varied with the 0.430 power. Both exponents differed from zero, but neither differed from the predicted value (0.5) at the 1 % level of significance. The teal continued to flap steadily as the tunnel tilt angle was varied from -1° (climb) to +6° (descent), while the wingbeat frequency declined progressively by about 11%. In both birds, the plot of wingbeat frequency against air speed in level flight was U-shaped, with small but statistically significant curvature. We identified the minima of these curves with the minimum power speed (Vmp) and found that the values predicted for Vmp, using previously published default values for the required variables, were only about two-thirds of the observed minimum-frequency speeds. The discrepancy could be resolved if the body drag coefficients (CDb) of both birds were near 0.08, rather than near 0.40 as previously assumed. The previously published high values for body drag coefficients were derived from wind-tunnel measurements on frozen bird bodies, from which the wings had been removed, and had long been regarded as anomalous, as values below 0.01 are given in the engineering literature for streamlined bodies. We suggest that birds of any size that have well-streamlined bodies can achieve minimum body drag coefficients of around 0.05 if the feet can be fully retracted under the flank feathers. In such birds, field observations of flight speeds may need to be reinterpreted in the light of higher estimates of Vmp. Estimates of the effective lift:drag ratio and range can also be revised upwards. Birds that have large feet or trailing legs may have higher body drag coefficients. The original estimates of around CDb=0.4 could be correct for species, such as pelicans and large herons, that also have prominent heads. We see no evidence for any progressive reduction of body drag coefficient in the Reynolds number range covered by our experiments, that is 21600-215 000 on the basis of body cross-sectional diameter.

Conditions favoring the formation of monomeric Pt(III) derivatives in the electrochemical oxidation of trans-[Pt(II){(p-BrC6F4)NCH2CH2NEt2}Cl(py)]

Characterization of the anticancer active compound trans-[Pt^II{(p-BrC6F4)NCH2CH2NEt2}Cl(py)] is described along with identification of electrochemical conditions that favor formation of a monomeric one-electron-oxidized Pt^III derivative. The square-planar organoamidoplatinum(II) compound was synthesized through a carbon dioxide elimination reaction. Structural characterization by using single-crystal X-Ray diffraction reveals a trans configuration with respect to donor atoms of like charges. As Pt^III intermediates have been implicated in the reactions of platinum anticancer agents, electrochemical conditions favoring the formation of one-electron-oxidized species were sought. Transient cyclic voltammetry at fast scan rates or steady-state rotating disc and microelectrode techniques in a range of molecular solvents and an ionic liquid confirm the existence of a well-defined, chemically and electrochemically reversible one-electron oxidation process that, under suitable conditions, generates a Pt^III complex, which is proposed to be monomeric [Pt^III{(p-BrC6F4)NCH2CH2NEt2}Cl(py)]⁺. Electron paramagnetic resonance spectra obtained from highly non-coordinating dichloromethane/([Bu4N][B(C6F5)4]) solutions, frozen to liquid nitrogen temperature immediately after bulk electrolysis in a glove box, support the Pt^III assignment rather than formation of a Pt^II cation radical. However, the voltammetric behavior is highly dependent on the timescale of the experiments, temperature, concentration of trans-[Pt^II{(p-BrC6F4)NCH2CH2NEt2}- Cl(py)], and the solvent/electrolyte. In the low-polarity solvent CH2Cl2 containing the very weakly coordinating electrolyte [Bu4N][B(C6F5)4], a well-defined reversible one-electron oxidation process is observed on relatively long timescales, which is consistent with the stabilization of the cationic platinum(III) complex in non-coordinating media. Bulk electrolysis of low concentrations of [Pt{(p-BrC6F4)NCH2CH2NEt2}Cl(py)] favors the formation of monomeric [Pt^III{(p-BrC6F4)NCH2CH2NEt2}Cl(py)]⁺. Simulations allow the reversible potential of the Pt^II/Pt^III process and the diffusion coefficient of [Pt^III{(p-BrC6F4)- NCH2CH2NEt2}Cl(py)]⁺ to be calculated. Reversible electrochemical behavior, giving rise to monomeric platinum(III) derivatives, is rare in the field of platinum chemistry.

Chip formation mechanism and machinability of wrought duplex stainless steel alloys

This paper investigates the chip formation mechanism and machinability of two-phase materials, such as, wrought duplex stainless steel alloys SAF 2205 and SAF 2507. SEM and optical microscopic details of the frozen cutting zone and chips revealed that the harder austenite phase dissipates in the advancement of the cutting tool, being effectively squeezed out of the softer ferrite phase. Microhardness profiles reveal correlation in hardness from the workpiece material transitioning to the chip. The tool wear (TiAIN + TiN coated solid carbide twist drill) and machining forces were investigated. Tool wear, was dominantly due to the adhesion process which developed from built-up edge formation, is highly detrimental to the flank face. Flute damage was also observed as a major issue in the drilling of duplex alloys leading to premature tool failure. Duplex 2507 shows higher sensitivity to cutting speed during machining and strain hardening at higher velocity and less machinability due to presence of higher percentage of Ni, Mo and Cr.

Indigenous blood and ethical regimes in the United States and Australia since the 1960s

Blood samples collected from members of indigenous communities in the mid-20th century by scientists interested in human variation remain frozen today in institutional repositories around the world. This article focuses on two such collections-one established and maintained in the United States and the other in Australia. Through historical and ethnographic analysis, we show how scientific knowledge about the human species and ethical knowledge about human experimentation are coproduced differently in each national context over time. Through a series of vignettes, we trace the attempts of scientists and indigenous people to assemble and reassemble blood samples, ethical regimes, human biological knowledge, and personhood. In including ourselves-a U.S. historian of science and an Australian anthropologist-in the narrative, we show how humanistic and social scientific analysis contributes to ongoing efforts to maintain indigenous samples. [indigenous, biospecimens, science, genomics, postcolonial, ethics, cryopreservation].