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Giraffe (Giraffa spp.) numbers and their habitat have drastically declined throughout Africa over the last century due to various threats linked to anthropogenic impacts including habitat loss and fragmentation, disease, poaching, and climate change. In Kenya, the Nubian giraffe (G. camelopardalis camelopardalis) population decreased significantly up until the late 1980s. As a result of increased conservation efforts, the Nubian giraffe population has rebounded since the early 1990s, however, it remains predominantly extralimital and/or restricted to closed protected areas in central and western Kenya. In this paper, we set out to assess historical and current population numbers and trends of Nubian giraffe in Kenya, and highlight the conservation efforts that are applied to conserve this Critically Endangered taxon. We reviewed published manuscripts and grey literature, wildlife authority records and interviewed landowners with Nubian giraffe populations. We also conducted photographic surveys in three national parks and reserves where anecdotal reports suggested that the largest populations of Nubian giraffe occurred. We found that from a low of 130 individuals remaining in the wild and near extinction in the mid-1970s, the Nubian giraffe population has rebounded to 1,042 in 14 populations in Kenya, which represents an increase of more than 700%. This conservation success story is attributed to targeted management efforts, in particular conservation translocations and the increased monitoring of populations. At the same time, various factors including habitat loss and fragmentation, and infrastructure developments, linked with the increasing human population continue to pose a threat to their survival in the country. We place our findings in the broader context of population ecology and present opportunities for conservation research as well as recommendations that inform the management of this critical population of concern. [ABSTRACT FROM AUTHOR]

The surface adhesion between C. elegans and the agar plates on which they are commonly grown has yet to be accurately quantified. C. elegans is a scientifically important species of nematode whose simple structure allowed the first mapping of the complete nervous system in a multicellular organism. One of the current topics of research in the C. elegans community is the investigation of neuronal function in locomotion. Models of locomotion are used in these studies to aid in determination of the functions of specific neurons involved in locomotion. The adhesion force plays a critical role in developing these models. This paper presents the experimental determination of the adhesion energy of a representative sample of C. elegans. Adhesion energy was determined by a direct pull-off technique. In this approach, nematodes are anesthetized to prevent movement and secured to a small load cell before an agar plate is slowly brought into contact with the specimen and then removed. The maximum tensile force is then fit to a JKR-type adhesion model, which assumes that the nematode is a cylinder in order to determine the adhesion energy. Repeated adhesions are also investigated to determine the importance of drying on the measured adhesion force. From these experiments, the adhesion energy was found to be W = 4.94 ± 1.19 mJ/m2. Limited experiments on the rol-6 cuticle mutant found a lower adhesion energy W = 2.65 ± 1.16 mJ/m2 for these animals. [ABSTRACT FROM AUTHOR]

In 2012, the orchid mealy bug Pseudococcus microcirculuswas first detected in situ in North America's more diverse orchid region, the Big Cypress Basin (Collier Co FL). A follow-up survey showed that the mealy bug is more widespread and found on epiphytic orchids in two locations, in both the Fakahatchee Strand State Preserve (sites B and F) and the Florida Panther National Wildlife Refuge (sites M and C). There, we collected mealy bugs ( n=54) from 35 orchid individuals and screened allelic variation at seven microsatellite loci. We estimated genetic diversity and differentiation among all sites and compared the variation among individuals collected on the same plant. Genetic differentiation between sites M and C ( F =0.03, P<0.01) and, M and B ( F =0.04, P<0.01) was detected. We also detected significantly lower mean pairwise relatedness among individuals from site B compared to all the other locations, and this population had the lowest inbreeding coefficient. Genetic diversity and mean pairwise relatedness were highly variable among plants with multiple individuals; however, plants from sites F and M tend to have collections of individuals with higher mean pairwise relatedness compared to sites B and C. Our results indicate that there is genetic diversity and differentiation among mealy bugs in these locations, and that collections of individuals on the same plant are genetically diverse. As such, the mealy bugs throughout these areas are likely to be genetically diverse and exist in multiple distinct populations. [ABSTRACT FROM AUTHOR]

Background:Black women have lower visceral adipose tissue (VAT) but are less insulin sensitive than white women; the mechanisms responsible are unknown.Objective:The study aimed to test the hypothesis that variation in subcutaneous adipose tissue (SAT) sensitivity to glucocorticoids might underlie these differences.Methods:Body fatness (dual energy X-ray absorptiometry) and distribution (computerized tomography), insulin sensitivity (SI, intravenous and oral glucose tolerance tests), and expression of 11β-hydroxysteroid dehydrogenase-1 (11HSD1), hexose-6-phosphate dehydrogenase and glucocorticoid receptor-α (GRα), as well as genes involved in adipogenesis and inflammation were measured in abdominal deep SAT, superficial SAT and gluteal SAT (GLUT) depots of 56 normal-weight or obese black and white premenopausal South African (SA) women. We used a combination of univariate and multivariate statistics to evaluate ethnic-specific patterns in adipose gene expression and related body composition and insulin sensitivity measures.Results:Although 11HSD1 activity and mRNA did not differ by ethnicity, GRα mRNA levels were significantly lower in SAT of black compared with white women, particularly in the GLUT depot (0.52±0.21 vs 0.91±0.26 AU, respectively, P<0.01). In black women, lower SAT GRα mRNA levels were associated with increased inflammatory gene transcript levels and abdominal SAT area, and reduced adipogenic gene transcript levels, VAT/SAT ratio and SI. Abdominal SAT 11HSD1 activity associated with increased VAT area and decreased SI in white, but not in black women.Conclusions:In black SA women, downregulation of GRα mRNA levels with obesity and reduced insulin sensitivity, possibly via increased SAT inflammation, is associated with reduced VAT accumulation. [ABSTRACT FROM AUTHOR]

Purpose: The purposes of this study were to assess the working definition of a colorectal anastomotic leak among colorectal surgeons and to survey the current approach to investigation and management of a patient with a suspected anastomotic leak. Methods: Online survey consisting of nine questions regarding the definition, assessment and investigation of anastomotic leaks was conducted. Of the 738 eligible ACP members contacted, 210 responded (28.4 %). Results: Results demonstrated that 94.2 % of surgeons agreed 'extravasation of contrast on enema' and 91.8 % agreed 'faecal material seen in drains/from the wound' constituted a clinical leak. Only 69.2 % agreed that a leak was 'intra-abdominal sepsis requiring a laparotomy', and about half agreed that radiological collections constituted a leak when either treated with antibiotics (46.6 %) or with percutaneous drainage (51.4 %). Serial clinical examination was the perceived most sensitive clinical feature for a leak, with 75 % of surgeons ranking this in their top three choices. Surgeons radiologically confirm a leak on average in 80.2 % of cases. A CT with rectal contrast for a left-sided leak was selected by 42.9 % of respondents. For a right-sided/small bowel anastomosis, 44.5 % selected a CT with oral contrast and 43.4 % a CT with IV contrast. Conclusions: There is still significant heterogeneity between surgeons in what they define as an anastomotic leak. Most surgeons valued clinical examination as the most sensitive initial tool for leak detection; however, radiology has a major role in the confirmation of clinical leaks in colorectal patients. There is an increasing need to be able to classify and grade anastomotic leaks, both to improve the care of patients and for audit purposes. [ABSTRACT FROM AUTHOR]

The influence of Ti and C on the solidification microstructure of Fe-10Al-5Cr (all composition values in weight percent) alloys was examined with solidification modeling and a variety of experimental techniques. Several Fe-10Al-5Cr-Ti-C alloys were fabricated using the arc button melting process and characterized using quantitative image analysis and electron microscopy techniques. The experimental alloys exhibited primary ferrite dendrites with an interdendritic ferrite/TiC eutectic constituent, and the amount of eutectic was affected by the Ti and C concentrations. A liquidus projection and primary solidification paths were calculated for the Fe-10Al-5Cr-Ti-C system in order to estimate the amount of TiC that is expected to form during solidification. The range in the calculated amount of TiC-containing eutectic matched the experimentally measured values reasonably well. The ability to control the amount of TiC that forms during solidification of an Fe-10Al-5Cr-Ti-C-based alloy shows promise for developing corrosion-resistant weld overlay claddings with resistance to hydrogen cracking. [ABSTRACT FROM AUTHOR]

A controversy exists between vertical mammoplasty and the “traditional” keyhole\inferior pedicle method of breast reduction. This article examines factors affecting breast projection by considering the difference in concept between vertical mammaplasty (using the modification proposed by Hall-Findley as an example) and the inferior pedicle\keyhole pattern. This article is not about “how to do” but rather about “why” things are done in a certain way. The emphasis is on understanding what is done and its effects rather than on technique. The breast can be considered a cone. Breast projection then is the ratio between the nipple projection and the breast base. Two key concepts need to be considered: the orientation of the ellipses during excision of breast tissue in breast reduction and the role of the breast base\inframammary fold. Breast projection is not determined by the scars. After an examination of each technique, methods to enhance projection are discussed. [ABSTRACT FROM AUTHOR]

Experimental data on the separation of synthetic and natural peptides are presented as treated in terms of the separation model proposed by the authors, which allows for the chain connectivity of amino acid residues and the cooperative character of their interaction with the surface. It was shown that the model accurately predicts the separation of peptides with identical amino acid contents and different sequences of units in the chain. The differences in the sequence may be permutation of amino acid residues and the presence of terminal groups, amino acid isomers, or mirror sequences in the chain. The separation model was used to predict the retention times of peptides prepared via the enzymatic hydrolysis of E. coli proteins and bovine serum albumin with trypsin. It was shown that in general the model accurately explains the array of experimental data on the separation of such peptides, thus being the first successful attempt to relate the chain sequence to the retention volume. [ABSTRACT FROM AUTHOR]

The J-integral fracture toughness and tensile behavior of AL-6XN (ATI Properties Inc., Pittsburgh, PA, USA) plate material in the short-transverse (S-T) orientation was studied. The material was tested with respect to the presence or absence of microstructural 'packets' of brittle sigma phase (σ-phase) particles within the austenite matrix, located near the centerline of the plate. The J-integral-fracture resistance curve (J-R-curve) qualitatively indicated that the presence of the σ-phase packets is a detriment to the fracture toughness of the material in the S-T orientation. Tensile specimens containing the packets of σ-phase particles exhibited reduced yield and tensile strengths as well as pronounced reduction in ductility compared to specimens nominally free of σ-phase packets. Particle cracking was observed within the σ-phase packets, which lead to premature fracture. This limited the ability of the material to plastically deform and work-harden, thereby accounting for the observed reductions in ductility, toughness, and ultimate tensile strength. [ABSTRACT FROM AUTHOR]

ATM and ATR are two related kinases essential for signalling DNA damage. Although ATM is thought to be the principle kinase responsible for signalling ionising radiation (IR)-induced DNA damage, ATR also contributes to signalling this form of genotoxic stress. However, the molecular basis of differential ATM and ATR activation in response to IR remains unclear. Here, we report that ATR is recruited to sites of IR-induced DNA damage significantly later than activation of ATM. We show that ATR is recruited to IR-induced nuclear foci in G1 and S phase of the cell cycle, supporting a role for ATR in detecting DNA damage outside of S phase. In addition, we report that recruitment of ATR to sites of IR-induced DNA damage is concomitant with appearance of large tracts of single-stranded DNA (ssDNA) and that this event is dependent on ATM and components of the Mre11/Rad50/Nbs1 (MRN) protein complex.Oncogene (2006) 25, 3894–3904. doi:10.1038/sj.onc.1209426; published online 13 February 2006 [ABSTRACT FROM AUTHOR]

Stepper motors are commonly used in low-cost open-loop positioning control systems. However, acceleration and deceleration are limited and operating open-loop can cause the loss of steps and stalling of the motor. To overcome these inherent problems, a low-cost minor closed-loop position control system was developed to optimise the torque output, maximise acceleration and deceleration rates and avoid the loss of steps. Two different minor closed-loop position controllers were designed and tested. Both systems employ an optical incremental encoder and both contain two feedback loops: a minor closed-loop (MCL) feeding back a step angle signal and a major closed-loop for position feedback. The first system uses a fixed advance angle MCL control whereas the second uses a fixed advance time MCL control involving a time-based interpolator. Details of these control strategies employed and the results obtained from the prototype systems are presented. [ABSTRACT FROM AUTHOR]

The article focuses on an evaluation study of the usefulness of Staphylococcus aureus serodiagnosis in clinical practice. The authors states that they identified the results of serum antistaphylolysin and anti-nuclease titres collected from individuals presenting to a 1,500-bed teaching hospital over a 3-year period.