Ecosystem Studies at Cedar Creek Natural History Area, III: Water Use Studies

Previous articles in this series (Lawrence et al. 1957-58, 1960) have dealt with the nature of ecosystems, history of the ecosystem analysis approach, and some of the objectives and the methods that have been used at the Cedar Creek Natural History Area of the University of Minnesota and the Minnesota Academy of Science. The area, which was acquired in large part through a generous grant from the Fleischmann Foundation, is located in Anoka and Isanti Counties in east central Minnesota. The work has been generously supported by the Hill Family Foundation since the early summer of 1957. One main objective has been to learn what becomes of the solar energy striking the landscape. It has been estimated from studies elsewhere that a rather large portion, probably over half of the energy which strikes a given level area, is expended in evaporation from non-living surfaces of open water and moist soil, and in transpiration from living plant surfaces. The combined vaporization is called evapotranspiration. The Cedar Creek area is especially well suited for studying these water losses, or uses as we shall consider them here, because such a large variety of surfaces occur in close proximity to one another, and because water surface is exposer in ponds and the water table is usually at the surface or within a few inches of the surface in willow, alder, and tamarack swamps

Analisis Biaya Diferensial dalam Pengambilan Keputusan Memproduksi Sendiri Atau Membeli Bahan Baku pada Rm. Bakso Ba Nyuk Nyang Manado

Perkembangan ilmu pengetahuan dan teknologi berdampak pada persaingan dunia usaha yang semakin ketat, baik Perusahaan yang bergerak di bidang industri, perdagangan maupun jasa. Berhasil tidaknya Perusahaan dalam mencapai tujuannya tergantung pada manajemen Perusahaan tersebut, apakah manajemen suatu Perusahaan sudah mampu mencapai tujuan Perusahaan sebenarnya, baik itu jangka pendek maupun jangka panjang. Sehingga dalam menjalankan kegiatan suatu Perusahaan, maka seringkali manajemen dihadapkan pada beberapa pilihan atau alternatif dari aktivitas yang dilakukan. Analisis biaya diferensial sangat diperlukan sesuai dengan masalah yang dihadapi oleh Perusahaan dalam usaha meningkatkan laba dan mengurangi kerugian. Biaya diferensial didefinisikan sebagai perbedaan biaya yang timbul akibat adanya keputusan tertentu. Tujuan penelitian ini untuk menganalisis biaya diferensial dalam pengambilan keputusan memproduksi sendiri atau membeli bahan baku pada RM. Bakso Ba Nyuk-Nyang Manado. Metode analisis yang digunakan adalah metode deskriptif kuantitatif. Hasil penelitian dilihat dari biaya diferensial menunjukan biaya yang akan dikeluarkan lebih kecil apabila pihak manajemen memproduksi sendiri dari pada membeli dari pemasok. Sebaiknya pimpinan RM. Bakso Ba Nyuk-Nyang, memproduksi mie sendiri karena lebih menguntungkan dan juga dapat menghemat biaya. Kata kunci: biaya diferensial, produksi bahan bak

Sow body condition at weaning and reproduction performance in organic piglet production

The objective was to investigate the variation in backfat at weaning and its relations to reproduction results in organic sow herds in Denmark. The study included eight herds and 573 sows. The average backfat at weaning mean�13 mm; SD�4.2 mm) ranging from 10.5 to 17.3 mm among herds shows that it is possible to avoid poor body condition at weaning even with a lactation length of seven weeks or more. No main effect of backfat at weaning on reproduction performance was found, but the probability of a successful reproduction after weaning tended to decrease with decreasing backfat for first parity sows, whereas the opposite was the case for multiparous sows

Recovering 6D Object Pose: A Review and Multi-modal Analysis

A large number of studies analyse object detection and pose estimation at visual level in 2D, discussing the effects of challenges such as occlusion, clutter, texture, etc., on the performances of the methods, which work in the context of RGB modality. Interpreting the depth data, the study in this paper presents thorough multi-modal analyses. It discusses the above-mentioned challenges for full 6D object pose estimation in RGB-D images comparing the performances of several 6D detectors in order to answer the following questions: What is the current position of the computer vision community for maintaining "automation" in robotic manipulation? What next steps should the community take for improving "autonomy" in robotics while handling objects? Our findings include: (i) reasonably accurate results are obtained on textured-objects at varying viewpoints with cluttered backgrounds. (ii) Heavy existence of occlusion and clutter severely affects the detectors, and similar-looking distractors is the biggest challenge in recovering instances' 6D. (iii) Template-based methods and random forest-based learning algorithms underlie object detection and 6D pose estimation. Recent paradigm is to learn deep discriminative feature representations and to adopt CNNs taking RGB images as input. (iv) Depending on the availability of large-scale 6D annotated depth datasets, feature representations can be learnt on these datasets, and then the learnt representations can be customized for the 6D problem

Genetic risk factors for postoperative atrial fibrillation—a nationwide genome-wide association study (GWAS)

BackgroundAtrial fibrillation (AF) is a major cause of morbidity with a high prevalence among the elderly and has an established genetic disposition. Surgery is a well-known risk factor for AF; however, it is currently not recognized how much common genetic variants influence the postoperative risk. The purpose of this study was to identify Single Nucleotide Polymorphisms associated with postoperative AF.MethodsThe UK Biobank was utilized to conduct a Genome-Wide Association Study (GWAS) to identify variants associated with AF after surgery. An initial discovery GWAS was performed in patients that had undergone surgery with subsequent replication in a unique non-surgical cohort. In the surgical cohort, cases were defined as newly diagnosed AF within 30 days after surgery. The threshold for significance was set at 5 × 10−8.ResultsAfter quality control, 144,196 surgical patients with 254,068 SNPs were left for analysis. Two variants (rs17042171 (p = 4.86 × 10−15) and rs17042081 (p = 7.12 × 10−15)) near the PITX2-gene reached statistical significance. These variants were replicated in the non-surgical cohort (1.39 × 10−101 and 1.27 × 10−93, respectively). Several other loci were significantly associated with AF in the non-surgical cohort.ConclusionIn this GWAS-analysis of a large national biobank, we identified 2 variants that were significantly associated with postoperative AF. These variants were subsequently replicated in a unique non-surgical cohort. These findings bring new insight in the genetics of postoperative AF and may help identify at-risk patients and guide management

Cell Death of Melanophores in Zebrafish trpm7 Mutant Embryos Depends on Melanin Synthesis

Transient receptor potential melastatin 7 (TRPM7) is a broadly expressed, non-selective cation channel. Studies in cultured cells implicate TRPM7 in regulation of cell growth, spreading, and survival. However, zebrafish trpm7 homozygous mutants display death of melanophores and temporary paralysis, but no gross morphological defects during embryonic stages. This phenotype implies that melanophores are unusually sensitive to decreases in Trpm7 levels, a hypothesis we investigate here. We find that pharmacological inhibition of caspases does not rescue melanophore viability in trpm7 mutants, implying that melanophores die by a mechanism other than apoptosis. Consistent with this possibility, ultrastructural analysis of dying melanophores in trpm7 mutants reveals abnormal melanosomes and evidence of a ruptured plasma membrane, indicating that cell death occurs by necrosis. Interestingly, inhibition of melanin synthesis largely prevents melanophore cell death in trpm7 mutants. These results suggest that melanophores require Trpm7 in order to detoxify intermediates of melanin synthesis. We find that unlike TRPM1, TRPM7 is expressed in human melanoma cell lines, indicating that these cells may also be sensitized to reduction of TRPM7 levels

Differentiation of Zebrafish Melanophores Depends on Transcription Factors AP2 Alpha and AP2 Epsilon

A model of the gene-regulatory-network (GRN), governing growth, survival, and differentiation of melanocytes, has emerged from studies of mouse coat color mutants and melanoma cell lines. In this model, Transcription Factor Activator Protein 2 alpha (TFAP2A) contributes to melanocyte development by activating expression of the gene encoding the receptor tyrosine kinase Kit. Next, ligand-bound Kit stimulates a pathway activating transcription factor Microphthalmia (Mitf), which promotes differentiation and survival of melanocytes by activating expression of Tyrosinase family members, Bcl2, and other genes. The model predicts that in both Tfap2a and Kit null mutants there will be a phenotype of reduced melanocytes and that, because Tfap2a acts upstream of Kit, this phenotype will be more severe, or at least as severe as, in Tfap2a null mutants in comparison to Kit null mutants. Unexpectedly, this is not the case in zebrafish or mouse. Because many Tfap2 family members have identical DNA–binding specificity, we reasoned that another Tfap2 family member may work redundantly with Tfap2a in promoting Kit expression. We report that tfap2e is expressed in melanoblasts and melanophores in zebrafish embryos and that its orthologue, TFAP2E, is expressed in human melanocytes. We provide evidence that Tfap2e functions redundantly with Tfap2a to maintain kita expression in zebrafish embryonic melanophores. Further, we show that, in contrast to in kita mutants where embryonic melanophores appear to differentiate normally, in tfap2a/e doubly-deficient embryonic melanophores are small and under-melanized, although they retain expression of mitfa. Interestingly, forcing expression of mitfa in tfap2a/e doubly-deficient embryos partially restores melanophore differentiation. These findings reveal that Tfap2 activity, mediated redundantly by Tfap2a and Tfap2e, promotes melanophore differentiation in parallel with Mitf by an effector other than Kit. This work illustrates how analysis of single-gene mutants may fail to identify steps in a GRN that are affected by the redundant activity of related proteins

Evolution of Escherichia coli to 42 °C and Subsequent Genetic Engineering Reveals Adaptive Mechanisms and Novel Mutations.

Adaptive laboratory evolution (ALE) has emerged as a valuable method by which to investigate microbial adaptation to a desired environment. Here, we performed ALE to 42 °C of ten parallel populations of Escherichia coli K-12 MG1655 grown in glucose minimal media. Tightly controlled experimental conditions allowed selection based on exponential-phase growth rate, yielding strains that uniformly converged toward a similar phenotype along distinct genetic paths. Adapted strains possessed as few as 6 and as many as 55 mutations, and of the 144 genes that mutated in total, 14 arose independently across two or more strains. This mutational recurrence pointed to the key genetic targets underlying the evolved fitness increase. Genome engineering was used to introduce the novel ALE-acquired alleles in random combinations into the ancestral strain, and competition between these engineered strains reaffirmed the impact of the key mutations on the growth rate at 42 °C. Interestingly, most of the identified key gene targets differed significantly from those found in similar temperature adaptation studies, highlighting the sensitivity of genetic evolution to experimental conditions and ancestral genotype. Additionally, transcriptomic analysis of the ancestral and evolved strains revealed a general trend for restoration of the global expression state back toward preheat stressed levels. This restorative effect was previously documented following evolution to metabolic perturbations, and thus may represent a general feature of ALE experiments. The widespread evolved expression shifts were enabled by a comparatively scant number of regulatory mutations, providing a net fitness benefit but causing suboptimal expression levels for certain genes, such as those governing flagellar formation, which then became targets for additional ameliorating mutations. Overall, the results of this study provide insight into the adaptation process and yield lessons important for the future implementation of ALE as a tool for scientific research and engineering