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Background: Cardiomyocyte growth is coupled with active protein synthesis, which is one of the basic biological processes in living cells. However, it is unclear whether the unfolded protein response transducers and effectors directly take part in the control of protein synthesis. The connection between critical functions of the unfolded protein response in cellular physiology and requirements of multiple processes for cell growth prompted us to investigate the role of the unfolded protein response in cell growth and underlying molecular mechanisms., Methods: Cardiomyocyte-specific inositol-requiring enzyme 1α (IRE1α) knockout and overexpression mouse models were generated to explore its function in vivo. Neonatal rat ventricular myocytes were isolated and cultured to evaluate the role of IRE1α in cardiomyocyte growth in vitro. Mass spectrometry was conducted to identify novel interacting proteins of IRE1α. Ribosome sequencing and polysome profiling were performed to determine the molecular basis for the function of IRE1α in translational control., Results: We show that IRE1α is required for cell growth in neonatal rat ventricular myocytes under prohypertrophy treatment and in HEK293 cells in response to serum stimulation. At the molecular level, IRE1α directly interacts with eIF4G and eIF3, 2 critical components of the translation initiation complex. We demonstrate that IRE1α facilitates the formation of the translation initiation complex around the endoplasmic reticulum and preferentially initiates the translation of transcripts with 5' terminal oligopyrimidine motifs. We then reveal that IRE1α plays an important role in determining the selectivity and translation of these transcripts. We next show that IRE1α stimulates the translation of epidermal growth factor receptor through an unannotated terminal oligopyrimidine motif in its 5' untranslated region. We further demonstrate a physiological role of IRE1α-governed protein translation by showing that IRE1α is essential for cardiomyocyte growth and cardiac functional maintenance under hemodynamic stress in vivo., Conclusions: These studies suggest a noncanonical, essential role of IRE1α in orchestrating protein synthesis, which may have important implications in cardiac hypertrophy in response to pressure overload and general cell growth under other physiological and pathological conditions., Competing Interests: None.

Bacteriophage ϕX174 is a small icosahedral virus of the Microviridae with a rapid replication cycle. Previously, we found that in ϕX174 infections of Escherichia coli, the most highly upregulated host proteins are two small heat shock proteins, IbpA and IbpB, belonging to the HSP20 family, which is a universally conserved group of stress-induced molecular chaperones that prevent irreversible aggregation of proteins. Heat shock proteins were found to protect against ϕX174 lysis, but IbpA/B have not been studied. In this work, we disrupted the ibpA and ibpB genes and measured the effects on ϕX174 replication. We found that in contrast to other E. coli heat shock proteins, they are not necessary for ϕX174 replication; moreover, their absence has no discernible effect on ϕX174 fecundity. These results suggest IbpA/B upregulation is a response to ϕX174 protein expression but does not play a role in phage replication, and they are not Microviridae host factors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

The Malat1 (metastasis-associated lung adenocarcinoma transcript 1) long noncoding RNA is highly and broadly expressed in mammalian tissues, accumulating in the nucleus where it modulates expression and pre-mRNA processing of many protein-coding genes. In this issue of Genes & Development , Xiao and colleagues (doi:10.1101/gad.351557.124) report that a significant fraction of Malat1 transcripts in cultured mouse neurons are surprisingly exported from the nucleus. These transcripts are packaged with Staufen proteins in RNA granules and traffic down the lengths of neurites. They then can be released in a stimulus-dependent manner to be locally translated into a microprotein that alters neuronal gene expression patterns., (© 2024 Wright and Wilusz; Published by Cold Spring Harbor Laboratory Press.)

Background: Demand for lip filler injection continues to increase. Despite the current literature's acknowledgement of the role both venous and arterial vasculature play in minor and major side effects, research addressing the venous vasculature of the lower one-third of the face is scarce., Methods: A photographic analysis of the venous vasculature of 26 participants was performed using a vein transilluminator to display the venous flow around the perioral region. The data were analyzed for commonalities among participants and then compared with common lip filler injection techniques and locations., Results: Venous tributaries were identified in all patients, with slight variation in pattern, superior to the upper vermilion border between the nasolabial fold and philtral column on each side of the mouth. Venous tributaries were noted approximately 1 to 1.5 cm lateral to the oral commissures extending inferiorly to the chin and along the labiomental crease. Four areas of venous pooling were deemed significant: a small area approximately 2 mm superior to the Cupid's bow, along the middle tubercle of the upper lip, along the wet-dry line of the lower lip; and centrally along the vermilion border between the lower lip tubercles., Conclusions: Perioral venous mapping provides a guide for injectors performing lip enhancement procedures in identifying areas at risk for injury because of venous pooling. Avoiding these anatomically vulnerable regions can minimize the potential for inflammation and ecchymosis associated with intravenous injection and prevent dissatisfactory aesthetic results because of lumps, excessive bruising, swelling, or asymmetry., (Copyright © 2023 by the American Society of Plastic Surgeons.)

Background: Cesarean delivery is the most common major surgery worldwide. Noise in healthcare settings leads to impaired communication and concentration, and stress among healthcare providers. Limited information is available about noise at cesarean delivery., Objective: This study aimed to achieve a comprehensive analysis of noise that occurs during cesarean deliveries. Sound level meters are used to determine baseline noise levels and to describe the frequency of acute noise generated during a cesarean delivery that will cause a human startle response. Secondarily, we aimed to evaluate the effectiveness of a visual alarm system in mitigating excessive noise., Study Design: We completed a preintervention/postintervention observational study of noise levels during cesarean deliveries before and after introduction of a visual alarm system for noise mitigation between February 15, 2021 and August 26, 2021. There were 156 cases included from each study period. Sound pressure levels were analyzed by overall case median decibel levels and by time epoch for relevant phases of the operation. Rapid increases in noise events capable of causing a human startle response, "startle events," were detected by retrospective analysis, with quantification for baselines and analysis of frequency by case type. Median noise levels with interquartile ranges are presented. Data are compared between epochs and case characteristics with nonparametric 2-tailed testing., Results: The median acoustic pressure for all cesarean deliveries was 61.8 (58.8-65.9) (median [interquartile range]) dBA (A-weighted decibels). The median dBA for the full case time period was significantly higher in cases with neonatal intensive care unit team presence (62.1 [60.5-63.9]), admission to the neonatal intensive care unit (62.0 [60.4-63.9]), 5-minute Apgar score <7 (62.2 [61.1-64.3]), multiple gestations (62.6 [62.0-64.2]), and intraoperative tubal sterilization (62.8 [61.5-65.1]). The use of visual alarms was associated with a statistically significant reduction of median noise level by 0.7 dBA, from 61.8 (60.6-63.5) to 61.1 (59.8-63.7) dBA (P<.001)., Conclusion: The noise intensities recorded during cesarean deliveries were commonly at levels that affect communication and concentration, and above the safe levels recommended by the World Health Organization. Although noise was reduced by 0.7 dBA, the reduction was not clinically significant in reaching a discernible amount (a 3-dB change) or in reducing "startle events." Isolated use of visual alarms during cesarean deliveries is unlikely to be a satisfactory noise mitigation strategy., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Australopiths, a group of hominins from the Plio-Pleistocene of Africa, are characterized by derived traits in their crania hypothesized to strengthen the facial skeleton against feeding loads and increase the efficiency of bite force production. The crania of robust australopiths are further thought to be stronger and more efficient than those of gracile australopiths. Results of prior mechanical analyses have been broadly consistent with this hypothesis, but here we show that the predictions of the hypothesis with respect to mechanical strength are not met: some gracile australopith crania are as strong as that of a robust australopith, and the strength of gracile australopith crania overlaps substantially with that of chimpanzee crania. We hypothesize that the evolution of cranial traits that increased the efficiency of bite force production in australopiths may have simultaneously weakened the face, leading to the compensatory evolution of additional traits that reinforced the facial skeleton. The evolution of facial form in early hominins can therefore be thought of as an interplay between the need to increase the efficiency of bite force production and the need to maintain the structural integrity of the face.

Spatial visualization, the ability to mentally rotate three-dimensional (3D) images, plays a significant role in anatomy education. This study examines the impact of technical drawing exercises on the improvement of spatial visualization and anatomy education in a Neuroscience course. First-year medical students (n = 84) were randomly allocated into a control group (n = 41) or art-training group (n = 43). Variables including self-reported artistic drawing ability, previous technical drawing experience, or previous anatomy laboratory exposure were gathered. Participants who self-identified as artistic individuals were equally distributed between the two groups. Students in the art-training group attended four 1-hour sessions to solve technical drawing worksheets. All participants completed two Mental Rotations Tests (MRT), which were used to assess spatial visualization. Data were also collected from two neuroscience written examinations and an anatomical "tag test" practical examination. Participants in the art-training and control groups improved on the MRT. The mean of written examination two was significantly higher (P = 0.007) in the art-training group (12.95) than the control group (11.48), and higher (P = 0.027) in those without technical drawing experience (12.44) than those with (11.00). The mean of the anatomical practical was significantly higher (P = 0.010) in those without artistic ability (46.24) than those with (42.00). These results suggest that completing technical drawing worksheets may aid in solving anatomy-based written examination questions on complex brain regions, but further research is needed to determine its implication on anatomy practical scores. These results propose a simple method of improving spatial visualization in anatomy education., (© 2021 American Association for Anatomy.)

Estimates suggest billions of dollars are lost annually in the US due to fuel tax fraud. One method of fuel fraud is called "cocktailing" and involves blending products that are non-taxed, lower value, taxed at a lower rate, or unwanted/less-refined petroleum to diesel fuels. The goal of this study was to investigate compound specific isotope analysis (CSIA) using isotope ratio mass spectrometry (IRMS) for small aromatics contained in diesel fuel to determine whether this approach could be used to identify cocktailing and potentially fingerprint possible sources. However, the high chemical complexity of diesel fuels complicates CSIA owing to the need to fully separate individual compounds for effective isotope analysis. Therefore, different methods were investigated to selectively isolate aromatics for CSIA and evaluate these methods for isotopic fractionation. Analyses indicate that there is enough variability in isotopic ratios (δ 2 H and δ 13 C) between toluene samples obtained from different sources to use CSIA to differentiate/identify the origin of potential fuel adulterants. Three isolation methods were identified that provided sufficiently pure aromatic fractions for CSIA: selective solvent extraction, ionic liquid coated solid phase microextraction (SPME), and a combination of the two. However, due to the labor-intensive nature of selective solvent extraction, ionic liquid coated SPME represents the best method to quickly isolate aromatics from diesel fuel, without sacrificing selectivity or sensitivity. All methods tested can result in isotopic fractionation, but this can be compensated for by applying a correction factor. Furthermore, the chemical composition of a sample appeared to be important in the degree to which fractionation occurred during isolation. While the tested approaches for aromatic extraction from diesel showed promise, additional studies are required to refine and validate the methods prior to routine use in fuel cocktailing investigations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Modern genome-scale methods that identify new genes, such as proteogenomics and ribosome profiling, have revealed, to the surprise of many, that overlap in genes, open reading frames and even coding sequences is widespread and functionally integrated into prokaryotic, eukaryotic and viral genomes. In parallel, the constraints that overlapping regions place on genome sequences and their evolution can be harnessed in bioengineering to build more robust synthetic strains and constructs. With a focus on overlapping protein-coding and RNA-coding genes, this Review examines their discovery, topology and biogenesis in the context of their genome biology. We highlight exciting new uses for sequence overlap to control translation, compress synthetic genetic constructs, and protect against mutation., (© 2021. Springer Nature Limited.)

Omics-based technologies have revolutionized our understanding of the coding potential of the genome. In particular, these studies revealed widespread unannotated open reading frames (ORFs) throughout genomes and that these regions have the potential to encode novel functional (micro-)proteins and/or hold regulatory roles. However, despite their genomic prevalence, relatively few of these noncanonical ORFs have been functionally characterized, likely in part due to their under-recognition by the broader scientific community. The few that have been investigated in detail have demonstrated their essentiality in critical and divergent biological processes. As such, here we aim to discuss recent advances in understanding the diversity of noncanonical ORFs and their roles, as well as detail biologically important examples within the context of the mammalian genome., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Accurate and comprehensive identification of residual glycerides in biodiesel is an important part of fuel characterization due to the impact of glycerides on the fuel physicochemical properties. However, analysis of bound glycerol in biodiesel samples faces challenges due to lack of readily available standards of structurally complex glyceride species in nontraditional biodiesel feedstocks and a risk of misannotation in the presence of impurities in gas chromatographic separations. Here, we evaluate methane and isobutane chemical ionization-single quadrupole mass spectrometry combined with high-temperature gas chromatography separations for mapping monoacylglycerols, diacylglycerols, and triacylglycerols in biodiesel. Unlike electron impact ionization, which produces mostly in-source fragments, isobutane chemical ionization spectra of tetramethylsilyl-derivatized monoacylglycerols and diacylglycerols are dominated by molecular ions and M-SiO(CH 3 ) 3 + ions, which provide important diagnostic information. We demonstrate the utility of isobutane chemical ionization in identifying structurally complex glycerolipid standards as well as species in biodiesel samples from different plant and animal feedstocks.

Background: Masculinizing chest reconstruction is the most common gender-affirming surgery in transgender males. Despite the current literature's acknowledgment of the vital role that proper placement of the nipple-areola complex (NAC) plays in a masculine chest contour, there is still much debate regarding the best anatomical landmarks to achieve the desired result., Objectives: The primary aim of this study is to determine which landmarks for NAC placement can be applied across diverse body types and aid surgeons in creating a masculine chest., Methods: Twenty-five formaldehyde-embalmed male cadavers were analyzed by conducting various measurements of the NAC, nipple, and surrounding bony and muscular landmarks to identify the most consistent landmarks for proper NAC placement. Linear regression analyses were run to determine how the distance between nipple to respective landmarks varied based on antemortem body mass index (BMI), height, weight, and age., Results: The measurements for the inferior and lateral borders of the pectoralis major muscle (PMM) displayed the least amount of variance of all the anatomical landmarks studied. Additionally, there was no significant change in these pectoral measurements with varying BMI, height, weight, or age, indicating that these measurements are reliable landmarks for NAC placement across various body types. The average NAC placement in relation to the inferior and lateral borders of PMM was around 2.5 and 2.0 cm, respectively., Conclusions: Our cadaveric analysis indicates that aesthetically pleasing masculine chest results can be produced consistently across varying body types when adhering to a simple pectoral approach in NAC placement., (© 2021 The Aesthetic Society.)

Measuring host-bacteriophage dynamics is an important approach to understanding bacterial survival functions and responses to infection. The model Microviridae bacteriophage φX174 is endemic to the human gut and has been studied for over 70 years, but the host response to infection has never been investigated in detail. To address this gap in our understanding of this important interaction within our microbiome, we have measured host Escherichia coli C proteomic and transcriptomic response to φX174 infection. We used mass spectrometry and RNA sequencing (RNA-seq) to identify and quantify all 11 φX174 proteins and over 1,700 E. coli proteins, enabling us to comprehensively map host pathways involved in φX174 infection. Most notably, we see significant host responses centered on membrane damage and remodeling, cellular chaperone and translocon activity, and lipoprotein processing, which we speculate is due to the peptidoglycan-disruptive effects of the φX174 lysis protein E on MraY activity. We also observe the massive upregulation of small heat shock proteins IbpA/B, along with other heat shock pathway chaperones, and speculate on how the specific characteristics of holdase protein activity may be beneficial for viral infections. Together, this study enables us to begin to understand the proteomic and transcriptomic host responses of E. coli to Microviridae infections and contributes insights to the activities of this important model host-phage interaction. IMPORTANCE A major part of the healthy human gut microbiome is the Microviridae bacteriophage, exemplified by the model φX174 phage, and their E. coli hosts. Although much has been learned from studying φX174 over the last half-century, until this work, the E. coli host response to infection has never been investigated in detail. We reveal the proteomic and transcriptomic pathways differentially regulated during the φX174 infection cycle and uncover the details of a coordinated cellular response to membrane damage that results in increased lipoprotein processing and membrane trafficking, likely due to the phage antibiotic-like lysis protein. We also reveal that small heat shock proteins IbpA/B are massively upregulated during infection and that these holdase chaperones are highly conserved across the domains of life, indicating that reliance on them is likely widespread across viruses., (Copyright © 2021 Wright et al.)

The advent of mobile electroencephalography (mEEG) has created a means for large scale collection of neural data thus affording a deeper insight into cognitive phenomena such as cognitive fatigue. Cognitive fatigue - a neural state that is associated with an increased incidence of errorful performance - is responsible for accidents on a daily basis which at times can cost human lives. To gain better insight into the neural signature of cognitive fatigue in the present study we used mEEG to examine the relationship between perceived cognitive fatigue and human-event related brain potentials (ERPs) and electroencephalographic (EEG) oscillations in a sample of 1,000 people. As a secondary goal, we wanted to further demonstrate the capability of mEEG to accurately measure ERP and EEG data. To accomplish these goals, participants performed a standard visual oddball task on an Apple iPad while EEG data were recorded from a Muse EEG headband. Counter to traditional EEG studies, experimental setup and data collection was completed in less than seven minutes on average. An analysis of our EEG data revealed robust N200 and P300 ERP components and neural oscillations in the delta, theta, alpha, and beta bands. In line with previous findings we observed correlations between ERP components and EEG power and perceived cognitive fatigue. Further, we demonstrate here that a linear combination of ERP and EEG features is a significantly better predictor of perceived cognitive fatigue than any ERP or EEG feature on its own. In sum, our results provide validation of mEEG as a viable tool for research and provide further insight into the impact of cognitive fatigue on the human brain., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Krigolson, Hammerstrom, Abimbola, Trska, Wright, Hecker and Binsted.)

The biomechanical and adaptive significance of variation in craniodental and mandibular morphology in fossil hominins is not always clear, at least in part because of a poor understanding of how different feeding behaviors impact feeding system design (form-function relationships). While laboratory studies suggest that ingestive behaviors produce variable loading, stress, and strain regimes in the cranium and mandible, understanding the relative importance of these behaviors for feeding system design requires data on their use in wild populations. Here we assess the frequencies and durations of manual, ingestive, and masticatory behaviors from more than 1400 observations of feeding behaviors video-recorded in a wild population of bearded capuchins (Sapajus libidinosus) at Fazenda Boa Vista in Piauí, Brazil. Our results suggest that ingestive behaviors in wild Sapajus libidinosus were used for a range of food material properties and typically performed using the anterior dentition. Coupled with previous laboratory work indicating that ingestive behaviors are associated with higher mandibular strain magnitudes than mastication, these results suggest that ingestive behaviors may play an important role in craniodental and mandibular design in capuchins and may be reflected in robust adaptations in fossil hominins.

Sequence overlap between two genes is common across all genomes, with viruses having high proportions of these gene overlaps. Genome modularization and refactoring is the process of disrupting natural gene overlaps to separate coding sequences to enable their individual manipulation. The biological function and fitness effects of gene overlaps are not fully understood, and their effects on gene cluster and genome-level refactoring are unknown. The bacteriophage φX174 genome has ∼26% of nucleotides involved in encoding more than one gene. In this study we use an engineered φX174 phage containing a genome with all gene overlaps removed to show that gene overlap is critical to maintaining optimal viral fecundity. Through detailed phenotypic measurements we reveal that genome modularization in φX174 causes virion replication, stability, and attachment deficiencies. Quantitation of the complete phage proteome across an infection cycle reveals 30% of proteins display abnormal expression patterns. Taken together, we have for the first time comprehensively demonstrated that gene modularization severely perturbs the coordinated functioning of a bacteriophage replication cycle. This work highlights the biological importance of gene overlap in natural genomes and that reducing gene overlap disruption should be an integral part of future genome engineering projects.

The purpose of this study was to correlate critical shoulder angle (CSA), a measurement that takes into account both glenoid tilt and the acromial index (AI), with shoulder pathologies as presented in an earlier study by Moor et al. (2013). Based on Moor et al.'s predicted normal CSA range of 30-35°, we hypothesized that a greater-than-normal CSA would be correlated to or associated with rotator cuff pathology, while a smaller-than-normal CSA would be associated with osteoarthritis (OA). Following Moore et al., we utilized Grashey radiographic imaging because it provides the clearest view of the entire glenoid fossa and acromion. We analyzed 323 anterior-posterior (AP) radiographs to identify and measure the CSA, classifying each patient into one of five groups [none reported (n=94), mild OA (n=156), moderate OA (n=36), severe OA (n=37), and rotator cuff pathology (n=40)]. Our results were statistically significant, supporting the association of smaller CSAs with OA and larger CSAs with rotator cuff pathology. CSA measurements could provide a new means for identifying shoulder pathology and thereby reduce the need for costly and timely imaging techniques. CSA values could also provide useful information to utilize preventatively with interventions such as physical therapy to alter the CSA and reduce the prevalence of OA and shoulder arthroplasties. This study builds on the findings of Moore et al. in creating a correlation between CSA and shoulder pathology., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2020, Rose-Reneau et al.)

Gas chromatography (GC) is undoubtedly the analytical technique of choice for compositional analysis of petroleum-based fuels. Over the past twenty years, as comprehensive two-dimensional gas chromatography (GC × GC) has evolved, fuel analysis has often been highlighted in scientific reports, since the complexity of fuel analysis allows for illustration of the impressive peak capacity gains afforded by GC × GC. Indeed, several research groups in recent years have applied GC × GC and chemometric data analysis to demonstrate the potential of these analytical tools to address important compliance (tax evasion, tax credits, physical quality standards) and forensic (arson investigations, oil spills) applications involving fuels. None the less, routine use of GC × GC in forensic laboratories has been limited largely by (1) legal and regulatory guidelines, (2) lack of chemometrics training, and (3) concerns about the reproducibility of GC × GC. The goal of this review is to highlight recent advances in one-dimensional GC (1D-GC) and GC × GC analyses of fuels for compliance and forensic applications, to assist scientists in overcoming the aforementioned hindrances. An introduction to 1D-GC principles, GC × GC technology (column stationary phases and modulators) and several chemometric methods is provided. More specifically, chemometric methods will be broken down into (1) signal preprocessing, (2) peak decomposition, identification and quantification, and (3) classification and pattern recognition. Examples of compliance and forensic applications will be discussed with particular emphasis on the demonstrated success of the employed chemometric methods. This review will hopefully make 1D-GC and GC × GC coupled with chemometric data analysis tools more accessible to the larger scientific community, and aid in eventual widespread standardization., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: This work was supported by the Internal Revenue Service (IRS) under an Interagency Agreement with the U.S. Department of Energy (DOE) under Contract DE-AC05-76RLO 1830. Pacific Northwest National Laboratory is operated by Battelle Memorial Institute. The views, opinions, and findings contained within this report are those of the authors and should not be construed as an official position, policy, or decision of the DOE or IRS unless designated by other documentation., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Introduction: Reports from the current literature show a lack of detail with depictions of the genicular arteries (GA). The intricate anatomy and infrequency of operating in the posterior knee may lead to surgeons being unfamiliar with the anatomy. The goal of this cadaveric study was to quantitatively map the arteries and create a caution zone that can be utilized when preparing and performing surgical procedures involving the knee., Materials and Methods: The left knees of 46 cadavers were used. The distance of the GAs were from the joint line (JL) (+, superior to JL; -, inferior to JL) was measured in two locations: popliteal artery (PA) branch point and medial/lateral knee. The angle the artery traveled between these two points in the posterior knee was measured. A caution map was created., Results: The superolateral GA branched from PA at +47.3 mm and traveled superiorly at 57.7° to +52.2 mm at the lateral knee. The superomedial GA branched from PA at +55.2 mm and traveled superiorly at 66.8° to +57.3 mm at the medial knee. The inferolateral GA branched from PA at -0.6 mm. It traveled superiorly at 74.1° or inferiorly at 62.1° to -1.0 mm at the lateral knee. The inferomedial GA branched from the PA at +9.9 mm. It traveled inferiorly at 21.2° to -33 mm at the medial knee., Conclusion: The GAs have a predictable pattern of location in the knee. There is a mismatch between medical textbooks and reality regarding arterial depictions. Knowledge regarding where the arteries are located may help reduce vascular complications in patients in the future., (© 2019 Wiley Periodicals, Inc.)

Reconstructing diet is critical to understanding hominin adaptations. Isotopic and functional morphological analyses of early hominins are compatible with consumption of hard foods, such as mechanically-protected seeds, but dental microwear analyses are not. The protective shells surrounding seeds are thought to induce complex enamel surface textures characterized by heavy pitting, but these are absent on the teeth of most early hominins. Here we report nanowear experiments showing that the hardest woody shells - the hardest tissues made by dicotyledonous plants - cause very minor damage to enamel but are themselves heavily abraded (worn) in the process. Thus, hard plant tissues do not regularly create pits on enamel surfaces despite high forces clearly being associated with their oral processing. We conclude that hard plant tissues barely influence microwear textures and the exploitation of seeds from graminoid plants such as grasses and sedges could have formed a critical element in the dietary ecology of hominins.

The study of adaptation requires the integration of an array of different types of data. A single individual can find such integration daunting, if not impossible. In an effort to clarify the role of diet in the evolution of the primate craniofacial and dental apparatus, we assembled a team of researchers that have various types and degrees of expertise. This interaction has provided a range of insights for all contributors, and this has helped to refine questions, clarify the possibilities and limitations that laboratory and field settings offer, and further explore the ways in which laboratory and field data can be suitably integrated. A complete and accurate picture of dietary adaptation cannot be gained in isolation. Collaboration provides the bridge to a more holistic view of primate biology and evolution., (© 2019 Wiley Periodicals, Inc.)

Using engineered initiator tRNA for precise control of protein translation within cells has great promise within future orthogonal translation systems to decouple housekeeping protein metabolism from that of engineered genetic systems. Previously, E. coli strain C321.ΔA. exp lacking all UAG stop codons was created, freeing this "amber" stop codon for other purposes. An engineered "amber initiator" tRNA CUA fMet that activates translation at UAG codons is available, but little is known about this tRNA's orthogonality. Here, we combine for the first time the amber initiator tRNA CUA fMet in C321.ΔA. exp and measure its cellular effects. We found that the tRNA CUA fMet expression resulted in a nearly 200-fold increase in fluorescent reporter expression with a unimodal population distribution and no apparent cellular fitness defects. Proteomic analysis revealed upregulated ribosome-associated, tRNA degradation, and amino acid biosynthetic proteins, with no evidence for off-target translation initiation. In contrast to previous work, we show that UAG-initiated proteins carry N-terminal methionine, but have no evidence for glutamine. Together, our results identify beneficial features of using the amber initiator tRNA CUA fMet to control gene expression while also revealing fundamental challenges to using engineered initiator tRNAs as the basis for orthogonal translation initiation systems.

Background: The opportunistic pathogen, Pseudomonas aeruginosa is well known for its environmental and metabolic versatility, yet many of the functions of its gene-products remain to be fully elucidated. This study's objective was to illuminate the potential functions of under-described gene-products during the medically relevant copper-stress condition., Results: We used data-independent acquisition mass spectrometry to quantitate protein expression changes associated with copper stress in P. aeruginosa PAO1. Approximately 2000 non-redundant proteins were quantified, with 78 proteins altering in abundance by +/- 1.5-fold or more when cultured to mid-log growth in the presence of 50 μM copper sulfate. One-third of those differentially expressed proteins have no prior established functional roles., Conclusions: This study provides evidence for the functional involvement of some specific proteins in enabling P. aeruginosa to survive under sub-lethal concentrations of copper. This further paves the way for targeted investigations into the specific mechanisms of their activity.

A modified version of the Direct LSC method to correct for quenching effect was investigated for the determination of bio-originated fuel content in fuel samples produced from multiple biological starting materials. The modified method was found to be accurate in determining the percent bio-originated fuel to within 5% of the actual value for samples with quenching effects ≤43%. Analysis of highly quenched samples was possible when diluted with the exception of one sample with a 100% quenching effect., (Copyright © 2017. Published by Elsevier Ltd.)

We report a quantitative approach to optimize implementation of discovery-based software for comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS). The software performs a tile-based Fisher ratio (F-ratio) analysis and facilitates a supervised nontargeted analysis based upon the experimental design to aid in the discovery of analytes with statistically different variances between sample classes. The quantitative approach for software optimization uses receiver operating characteristic (ROC) curves. The area under the curve (AUC) for each ROC curve serves as a quantitative metric to optimize two key algorithm parameters: the signal-to-noise ratio (S/N) threshold of the data prior to calculating F-ratios at each m/z mass channel and the number of these F-ratios per m/z used to calculate the average F-ratio of a tile. A total of 25 combinations of S/N threshold by number of m/z were studied. Fifty analytes were spiked into a diesel fuel at two concentration levels to produce two sample classes that should in principle produce 50 positive instances in the ROC curves. The "sweet spot" for F-ratio analysis was determined to be a S/N threshold of 10 coupled with a maximum of the 10 most chemically selective m/z (requiring a minimum of 3 m/z), corresponding to an ∼21% improvement in the discrimination of true positives relative to prior studies. This equates to an additional 9 true positives being discovered at a false positive probability of 0.2 and 5 additional true positives being found overall. Furthermore, optimization of these software parameters did not depend upon a priori determination of the statistically correct number of positive instances in the sample classes. The AUC metric appears to be suitable for the evaluation of all data analysis methods that utilize the proper experimental design.

Background: Current literature suggests that preserving the lobular branch of the great auricular nerve has greater impact on sensory function of the auricle than preservation of the posterior branch during rhytidectomy. However, no methodology exists to efficiently and accurately determine the topographic location of the lobular branch. This study describes the branching characteristics of the lobular branch and algorithmic surface markings to assist surgeons in preservation of the great auricular nerve during rhytidectomy flap elevation., Methods: The lobular branch was dissected in 50 cadaveric necks. Measurements were taken from the lobular branch to conchal cartilage, tragus, and antitragus. The anterior branch was measured to its superficial musculoaponeurotic system insertion, and the posterior branch was measured to the mastoid process. The McKinney point was marked and the great auricular nerve diameter was recorded. Branching pattern and location of branches within the Ozturk 30-degree angle were documented. Basic statistics were performed., Results: The lobular branch was present in all specimens and distributed to three regions. In 85 percent of specimens, the lobular branch resided directly inferior to the antitragus; in the remaining specimens, it was located directly inferior to the tragus. Preoperative markings consisting of two vertical lines from the tragus and antitragus to the McKinney point can be used to outline the predicted location of the lobular branch., Conclusions: This study delineates the location of the lobular branch of the great auricular nerve. The authors translate these findings into a quick and simple intraoperative marking, which can assist surgeons in avoiding lobular branch injury during rhytidectomy dissection.

Australopiths exhibit a number of derived facial features that are thought to strengthen the face against high and/or repetitive loads associated with a diet that included mechanically challenging foods. Here, we use finite element analysis (FEA) to test hypotheses related to the purported strengthening role of the zygomatic root and "anterior pillar" in australopiths. We modified our previously constructed models of Sts 5 (Australopithecus africanus) and MH1 (A. sediba) to differ in the morphology of the zygomatic root, including changes to both the shape and positioning of the zygomatic root complex, in addition to creating variants of Sts 5 lacking anterior pillars. We found that both an expanded zygomatic root and the presence of "anterior pillars" reinforce the face against feeding loads. We also found that strain orientations are most compatible with the hypothesis that the pillar evolved to resist loads associated with premolar loading, and that this morphology has an ancillary effect of strengthening the face during all loading regimes. These results provide support for the functional hypotheses. However, we found that an anteriorly positioned zygomatic root increases strain magnitudes even in models with an inflated/reinforced root complex. These results suggest that an anteriorly placed zygomatic root complex evolved to enhance the efficiency of bite force production while facial reinforcement features, such as the anterior pillar and the expanded zygomatic root, may have been selected for in part to compensate for the weakening effect of this facial configuration. Anat Rec, 300:171-195, 2017. © 2016 Wiley Periodicals, Inc., (© 2016 Wiley Periodicals, Inc.)

Background: This study aimed to identify the anterior and posterior extralaryngeal branches (AELB, PELB) of the recurrent laryngeal nerve (RLN), measure these branches when present, and determine relationships between gender, sidedness and neck length., Materials and Methods: Dissection was completed to level of the thyroid on 45 cadavers. The course of the RLN was then traced superiorly from its entry into the neck. Careful reflection of the thyroid and dissection of the lateral thyroid ligament permitted visualisation of the full course of the nerve. If extralaryngeal branching (ELB) was present, measurements were taken from the point of bifurcation of the RLN to the point of laryngeal entry through the cricothyroid membrane. Neck measurements, from the spinous process of C7 to the superior nuchal line, were taken. Gender of the specimen was noted. Data was analysed in SPSS., Results: Extralaryngeal branching was found in 77.78% of our sample, 77.14% on the left and 54.29% on the right. A significant difference was found between AELB length on the left and right, indicating that the left branch will be longer than the right when present. A significant difference in neck length between those with and without ELB was also found, indicating that people with longer necks more often display ELB. Neither neck length and AELB length, nor gender and AELB length were strongly correlated in this sample., Conclusions: Extralaryngeal branching can occur in all populations, but there are definite trends in its incidence and length. Surgeons should be aware of these trends before operating on patients.

Substantial variation exists in the mechanical properties of foods consumed by primate species. This variation is known to influence food selection and ingestion among non-human primates, yet no large-scale comparative study has examined the relationships between food mechanical properties and feeding strategies. Here, we present comparative data on the Young's modulus and fracture toughness of natural foods in the diets of 31 primate species. We use these data to examine the relationships between food mechanical properties and dietary quality, body mass, and feeding time. We also examine the relationship between food mechanical properties and categorical concepts of diet that are often used to infer food mechanical properties. We found that traditional dietary categories, such as folivory and frugivory, did not faithfully track food mechanical properties. Additionally, our estimate of dietary quality was not significantly correlated with either toughness or Young's modulus. We found a complex relationship among food mechanical properties, body mass, and feeding time, with a potential interaction between median toughness and body mass. The relationship between mean toughness and feeding time is straightforward: feeding time increases as toughness increases. However, when considering median toughness, the relationship with feeding time may depend upon body mass, such that smaller primates increase their feeding time in response to an increase in median dietary toughness, whereas larger primates may feed for shorter periods of time as toughness increases. Our results emphasize the need for additional studies quantifying the mechanical and chemical properties of primate diets so that they may be meaningfully compared to research on feeding behavior and jaw morphology., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The evolution of the modern human (Homo sapiens) cranium is characterized by a reduction in the size of the feeding system, including reductions in the size of the facial skeleton, postcanine teeth, and the muscles involved in biting and chewing. The conventional view hypothesizes that gracilization of the human feeding system is related to a shift toward eating foods that were less mechanically challenging to consume and/or foods that were processed using tools before being ingested. This hypothesis predicts that human feeding systems should not be well-configured to produce forceful bites and that the cranium should be structurally weak. An alternate hypothesis, based on the observation that humans have mechanically efficient jaw adductors, states that the modern human face is adapted to generate and withstand high biting forces. We used finite element analysis (FEA) to test two opposing mechanical hypotheses: that compared to our closest living relative, chimpanzees (Pan troglodytes), the modern human craniofacial skeleton is (1) less well configured, or (2) better configured to generate and withstand high magnitude bite forces. We considered intraspecific variation in our examination of human feeding biomechanics by examining a sample of geographically diverse crania that differed notably in shape. We found that our biomechanical models of human crania had broadly similar mechanical behavior despite their shape variation and were, on average, less structurally stiff than the crania of chimpanzees during unilateral biting when loaded with physiologically-scaled muscle loads. Our results also show that modern humans are efficient producers of bite force, consistent with previous analyses. However, highly tensile reaction forces were generated at the working (biting) side jaw joint during unilateral molar bites in which the chewing muscles were recruited with bilateral symmetry. In life, such a configuration would have increased the risk of joint dislocation and constrained the maximum recruitment levels of the masticatory muscles on the balancing (non-biting) side of the head. Our results do not necessarily conflict with the hypothesis that anterior tooth (incisors, canines, premolars) biting could have been selectively important in humans, although the reduced size of the premolars in humans has been shown to increase the risk of tooth crown fracture. We interpret our results to suggest that human craniofacial evolution was probably not driven by selection for high magnitude unilateral biting, and that increased masticatory muscle efficiency in humans is likely to be a secondary byproduct of selection for some function unrelated to forceful biting behaviors. These results are consistent with the hypothesis that a shift to softer foods and/or the innovation of pre-oral food processing techniques relaxed selective pressures maintaining craniofacial features that favor forceful biting and chewing behaviors, leading to the characteristically small and gracile faces of modern humans.

The illicit chemical alteration of petroleum fuels is of keen interest, particularly to regulatory agencies that set fuel specifications, or taxes/credits based on those specifications. One type of alteration is the reaction of diesel fuel with concentrated sulfuric acid. Such reactions are known to subtly alter the chemical composition of the fuel, particularly the aromatic species native to the fuel. Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS) is well suited for the analysis of diesel fuel, but may provide the analyst with an overwhelming amount of data, particularly in sample-class comparison experiments comprised of many samples. Tile-based Fisher-ratio (F-ratio) analysis reduces the abundance of data in a GC×GC-TOFMS experiment to only the peaks which significantly distinguish the unaltered and acid altered sample classes. Three samples of diesel fuel from differently branded filling stations were each altered to discover chemical features, i.e., analyte peaks, which were consistently changed by the acid reaction. Using different fuels prioritizes the discovery of features likely to be robust to the variation present between fuel samples and may consequently be useful in determining whether an unknown sample has been acid altered. The subsequent analysis confirmed that aromatic species are removed by the acid alteration, with the degree of removal consistent with predicted reactivity toward electrophilic aromatic sulfonation. Additionally, we observed that alkenes and alkynes were also removed from the fuel, and that sulfur dioxide or compounds that degrade to sulfur dioxide are generated by the acid alteration. In addition to applying the previously reported tile-based F-ratio method, this report also expands null distribution analysis to algorithmically determine an F-ratio threshold to confidently select only the features which are sufficiently class-distinguishing. When applied to the acid alteration of diesel fuel, the suggested per-hit F-ratio threshold was 12.4, which is predicted to maintain the false discovery rate (FDR) below 0.1%. Using this F-ratio threshold, 107 of the 3362 preliminary hits were deemed significantly changing due to the acid alteration, with the number of false positives estimated to be about 3. Validation of the F-ratio analysis was performed using an additional three fuels., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Australopithecus sediba has been hypothesized to be a close relative of the genus Homo. Here we show that MH1, the type specimen of A. sediba, was not optimized to produce high molar bite force and appears to have been limited in its ability to consume foods that were mechanically challenging to eat. Dental microwear data have previously been interpreted as indicating that A. sediba consumed hard foods, so our findings illustrate that mechanical data are essential if one aims to reconstruct a relatively complete picture of feeding adaptations in extinct hominins. An implication of our study is that the key to understanding the origin of Homo lies in understanding how environmental changes disrupted gracile australopith niches. Resulting selection pressures led to changes in diet and dietary adaption that set the stage for the emergence of our genus.

Objectives: The diet of tufted capuchins (Sapajus) is characterized by annual or seasonal incorporation of mechanically protected foods. Reliance on these foods raises questions about the dietary strategies of young individuals that lack strength and experience to access these resources. Previous research has demonstrated differences between the feeding competencies of adult and juvenile tufted capuchins. Here we test the hypothesis that, compared to adults, juveniles will process foods with lower toughness and elastic moduli., Materials and Methods: We present data on variation in the toughness and elastic modulus of food tissues processed by Sapajus libidinosus during the dry season at Fazenda Boa Vista, Brazil. Food mechanical property data were collected using a portable universal mechanical tester., Results: Results show that food tissues processed by the capuchins showed significant differences in toughness and stiffness. However, we found no relationship between an individual's age and mean or maximum food toughness or elastic modulus, indicating both juvenile and adult S. libidinosus are able to process foods of comparable properties., Discussion: Although it has been suggested that juveniles avoid mechanically protected foods, age-related differences in feeding competence are not solely due to variation in food toughness or stiffness. Other factors related to food type (e.g., learning complex behavioral sequences, achieving manual dexterity, obtaining physical strength to lift stone tools, or recognizing subtle cues about food state) combined with food mechanical properties better explain variation in juvenile feeding competency., (© 2015 Wiley Periodicals, Inc.)

Comprehensive two-dimensional (2D) gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS) is a versatile instrumental platform capable of collecting highly informative, yet highly complex, chemical data for a variety of samples. Fisher-ratio (F-ratio) analysis applied to the supervised comparison of sample classes algorithmically reduces complex GC × GC-TOFMS data sets to find class distinguishing chemical features. F-ratio analysis, using a tile-based algorithm, significantly reduces the adverse effects of chromatographic misalignment and spurious covariance of the detected signal, enhancing the discovery of true positives while simultaneously reducing the likelihood of detecting false positives. Herein, we report a study using tile-based F-ratio analysis whereby four non-native analytes were spiked into diesel fuel at several concentrations ranging from 0 to 100 ppm. Spike level comparisons were performed in two regimes: comparing the spiked samples to the nonspiked fuel matrix and to each other at relative concentration factors of two. Redundant hits were algorithmically removed by refocusing the tiled results onto the original high resolution pixel level data. To objectively limit the tile-based F-ratio results to only features which are statistically likely to be true positives, we developed a combinatorial technique using null class comparisons, called null distribution analysis, by which we determined a statistically defensible F-ratio cutoff for the analysis of the hit list. After applying null distribution analysis, spiked analytes were reliably discovered at ∼1 to ∼10 ppm (∼5 to ∼50 pg using a 200:1 split), depending upon the degree of mass spectral selectivity and 2D chromatographic resolution, with minimal occurrence of false positives. To place the relevance of this work among other methods in this field, results are compared to those for pixel and peak table-based approaches.

Purpose: To calculate the output factor (OPF) of any irregularly shaped electron beam at extended SSD., Methods: Circular cutouts were prepared from 2.0 cm diameter to the maximum possible size for 15 × 15 applicator cone. In addition, two irregular cutouts were prepared. For each cutout, percentage depth dose (PDD) at the standard SSD and doses at different SSD values were measured using 6, 9, 12, and 16 MeV electron beam energies on a Varian 2100C LINAC and the distance at which the central axis electron fluence becomes independent of cutout size was determined. The measurements were repeated with an ELEKTA Synergy LINAC using 14 × 14 applicator cone and electron beam energies of 6, 9, 12, and 15 MeV. The PDD measurements were performed using a scanning system and two diodes-one for the signal and the other a stationary reference outside the tank. The doses of the circular cutouts at different SSDs were measured using PTW 0.125 cm(3) Semiflex ion-chamber and EDR2 films. The electron fluence was measured using EDR2 films., Results: For each circular cutout, the lateral buildup ratio (LBR) was calculated from the measured PDD curve using the open applicator cone as the reference field. The effective SSD (SSDeff) of each circular cutout was calculated from the measured doses at different SSD values. Using the LBR value and the radius of the circular cutout, the corresponding lateral spread parameter [σR(z)] was calculated. Taking the cutout size dependence of σR(z) into account, the PDD curves of the irregularly shaped cutouts at the standard SSD were calculated. Using the calculated PDD curve of the irregularly shaped cutout along with the LBR and SSDeff values of the circular cutouts, the output factor of the irregularly shaped cutout at extended SSD was calculated. Finally, both the calculated PDD curves and output factor values were compared with the measured values., Conclusions: The improved LBR method has been generalized to calculate the output factor of electron therapy at extended SSD. The percentage difference between the calculated and the measured output factors of irregularly shaped cutouts in a clinical useful SSD region was within 2%. Similar results were obtained for all available electron energies of both Varian 2100C and ELEKTA Synergy machines.

Recent molecular work has confirmed the long-standing morphological hypothesis that capuchins are comprised of two distinct clades, the gracile (untufted) capuchins (genus Cebus, Erxleben, 1777) and the robust (tufted) capuchins (genus Sapajus Kerr, 1792). In the past, the robust group was treated as a single, undifferentiated and cosmopolitan species, with data from all populations lumped together in morphological and ecological studies, obscuring morphological differences that might exist across this radiation. Genetic evidence suggests that the modern radiation of robust capuchins began diversifying ∼2.5 Ma, with significant subsequent geographic expansion into new habitat types. In this study we use a morphological sample of gracile and robust capuchin craniofacial and postcranial characters to examine how ecology and evolutionary history have contributed to morphological diversity within the robust capuchins. We predicted that if ecology is driving robust capuchin variation, three distinct robust morphotypes would be identified: (1) the Atlantic Forest species (Sapajus xanthosternos, S. robustus, and S. nigritus), (2) the Amazonian rainforest species (S. apella, S. cay and S. macrocephalus), and (3) the Cerrado-Caatinga species (S. libidinosus). Alternatively, if diversification time between species pairs predicts degree of morphological difference, we predicted that the recently diverged S. apella, S. macrocephalus, S. libidinosus, and S. cay would be morphologically comparable, with greater variation among the more ancient lineages of S. nigritus, S. xanthosternos, and S. robustus. Our analyses suggest that S. libidinosus has the most derived craniofacial and postcranial features, indicative of inhabiting a more terrestrial niche that includes a dependence on tool use for the extraction of imbedded foods. We also suggest that the cranial robusticity of S. macrocephalus and S. apella are indicative of recent competition with sympatric gracile capuchin species, resulting in character displacement., (Copyright © 2014 Elsevier Inc. All rights reserved.)

In a broad range of evolutionary studies, an understanding of intraspecific variation is needed in order to contextualize and interpret the meaning of variation between species. However, mechanical analyses of primate crania using experimental or modeling methods typically encounter logistical constraints that force them to rely on data gathered from only one or a few individuals. This results in a lack of knowledge concerning the mechanical significance of intraspecific shape variation that limits our ability to infer the significance of interspecific differences. This study uses geometric morphometric methods (GM) and finite element analysis (FEA) to examine the biomechanical implications of shape variation in chimpanzee crania, thereby providing a comparative context in which to interpret shape-related mechanical variation between hominin species. Six finite element models (FEMs) of chimpanzee crania were constructed from CT scans following shape-space Principal Component Analysis (PCA) of a matrix of 709 Procrustes coordinates (digitized onto 21 specimens) to identify the individuals at the extremes of the first three principal components. The FEMs were assigned the material properties of bone and were loaded and constrained to simulate maximal bites on the P(3) and M(2) . Resulting strains indicate that intraspecific cranial variation in morphology is associated with quantitatively high levels of variation in strain magnitudes, but qualitatively little variation in the distribution of strain concentrations. Thus, interspecific comparisons should include considerations of the spatial patterning of strains rather than focus only on their magnitudes., (© 2014 Wiley Periodicals, Inc.)

The African Plio-Pleistocene hominins known as australopiths evolved derived craniodental features frequently interpreted as adaptations for feeding on either hard, or compliant/tough foods. Among australopiths, Paranthropus boisei is the most robust form, exhibiting traits traditionally hypothesized to produce high bite forces efficiently and strengthen the face against feeding stresses. However, recent mechanical analyses imply that P. boisei may not have been an efficient producer of bite force and that robust morphology in primates is not necessarily strong. Here we use an engineering method, finite element analysis, to show that the facial skeleton of P. boisei is structurally strong, exhibits a strain pattern different from that in chimpanzees (Pan troglodytes) and Australopithecus africanus, and efficiently produces high bite force. It has been suggested that P. boisei consumed a diet of compliant/tough foods like grass blades and sedge pith. However, the blunt occlusal topography of this and other species suggests that australopiths are adapted to consume hard foods, perhaps including grass and sedge seeds. A consideration of evolutionary trends in morphology relating to feeding mechanics suggests that food processing behaviors in gracile australopiths evidently were disrupted by environmental change, perhaps contributing to the eventual evolution of Homo and Paranthropus., (© 2014 Wiley Periodicals, Inc.)

Comprehensive two-dimensional (2D) gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS) is a highly capable instrumental platform that produces complex and information-rich multi-dimensional chemical data. The data can be initially overwhelming, especially when many samples (of various sample classes) are analyzed with multiple injections for each sample. Thus, the data must be analyzed in such a way as to extract the most meaningful information. The pixel-based and peak table-based Fisher ratio algorithmic approaches have been used successfully in the past to reduce the multi-dimensional data down to those chemical compounds that are changing between the sample classes relative to those that are not changing (i.e., chemical feature selection). We report on the initial development of a computationally fast novel tile-based Fisher-ratio software that addresses the challenges due to 2D retention time misalignment without explicitly aligning the data, which is often a shortcoming for both pixel-based and peak table-based algorithmic approaches. Concurrently, the tile-based Fisher-ratio algorithm significantly improves the sensitivity contrast of true positives against a background of potential false positives and noise. In this study, eight compounds, plus one internal standard, were spiked into diesel at various concentrations. The tile-based F-ratio algorithmic approach was able to "discover" all spiked analytes, within the complex diesel sample matrix with thousands of potential false positives, in each possible concentration comparison, even at the lowest absolute spiked analyte concentration ratio of 1.06, the ratio between the concentrations in the spiked diesel sample to the native concentration in diesel., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Recent biomechanical analyses examining the feeding adaptations of early hominins have yielded results consistent with the hypothesis that hard foods exerted a selection pressure that influenced the evolution of australopith morphology. However, this hypothesis appears inconsistent with recent reconstructions of early hominin diet based on dental microwear and stable isotopes. Thus, it is likely that either the diets of some australopiths included a high proportion of foods these taxa were poorly adapted to consume (i.e., foods that they would not have processed efficiently), or that aspects of what we thought we knew about the functional morphology of teeth must be wrong. Evaluation of these possibilities requires a recognition that analyses based on microwear, isotopes, finite element modeling, and enamel chips and cracks each test different types of hypotheses and allow different types of inferences. Microwear and isotopic analyses are best suited to reconstructing broad dietary patterns, but are limited in their ability to falsify specific hypotheses about morphological adaptation. Conversely, finite element analysis is a tool for evaluating the mechanical basis of form-function relationships, but says little about the frequency with which specific behaviors were performed or the particular types of food that were consumed. Enamel chip and crack analyses are means of both reconstructing diet and examining biomechanics. We suggest that current evidence is consistent with the hypothesis that certain derived australopith traits are adaptations for consuming hard foods, but that australopiths had generalized diets that could include high proportions of foods that were both compliant and tough., (Copyright © 2013 Wiley Periodicals, Inc.)

Humans can use hand tools smoothly and effectively in varying circumstances; in other words, skillfully. A few other species of primates crack encased foods using hammer tools and anvils. Are they skilled? Positioning the food on the anvil so that it does not fall off when struck is a component of skilled cracking. We discovered that bearded capuchin monkeys deliberately place palm nuts in a relatively stable position on the anvil before striking them. In the first experiment, we marked the meridians of palm nuts where they stopped when rolled on a flat surface ("Stop meridian"). We videotaped monkeys as they cracked these nuts on an anvil. In playback we coded the position of the Stop meridian prior to each strike. Monkeys typically knocked the nuts on the anvil a few times before releasing them in a pit. They positioned the nuts so that the Stop meridian was within 30 degrees of vertical with respect to gravity more often than expected, and the nuts rarely moved after the monkeys released them. In the second experiment, 14 blindfolded people (7 men) asked to position marked nuts on an anvil as if to crack them reliably placed them with the Stop meridian in the same position as the monkeys did. In the third experiment, two people judged that palm nuts are most bilaterally symmetric along a meridian on, or close to, the Stop meridian. Thus the monkeys reliably placed the more symmetrical side of the nuts against the side of the pit, and the nuts reliably remained stationary when released. Monkeys apparently used information gained from knocking the nut to achieve this position. Thus, monkeys place the nuts skillfully, strategically managing the fit between the variable nuts and pits in the anvil, and skilled placement depends upon information generated by manual action.

A novel method is described for the evaluation of irreversible adsorption and column bleed in gas chromatographic (GC) columns using a tandem GC approach. This work specifically determined the degree of irreversible adsorption behavior of specific sulfur and phosphorous containing test probe compounds at levels ranging from approximately 50 picograms (pg) to 1 nanogram (ng) on selected gas chromatographic columns. This method does not replace existing evaluation methods that characterize reversible adsorption but provides an additional tool. The test compounds were selected due to their ease of adsorption and their importance in the specific trace analytical detection methodology being developed. Replicate chromatographic columns with 5% phenylmethylpolysiloxane (PMS), polyethylene glycol (wax), trifluoropropylpolysiloxane (TFP), or 78% cyanopropylpolysiloxane stationary phases from a variety of vendors were evaluated. As expected, the results demonstrate that the different chromatographic phases exhibit differing degrees of irreversible adsorption behavior. The results also indicate that all manufacturers do not produce equally inert columns nor are columns from a given manufacturer identical. The wax-coated columns for the test probes used were more inert as a group than 5% PMS coated columns, and they were more reproducibly manufactured. Both TFP and 78% cyanopropylpolysiloxane columns displayed superior inertness to the test compounds compared to either 5% PMS- or wax-coated columns. Irreversible adsorption behavior was characterized for a limited range of stationary phase film thicknesses. In addition, the method was shown effective for characterizing column bleed and methods to remove bleed components. This method is useful in screening columns for demanding applications and to obtain diagnostic information related to improved preparation methods., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The purpose of this study was to perform a preliminary investigation of compound-specific isotope analysis (CSIA) of diesel fuels to evaluate whether the technique could distinguish diesel samples from different sources/locations. The ability to differentiate or correlate diesel samples could be valuable for discovering fuel tax evasion schemes or for environmental forensic studies. Two urea adduction-based techniques were used to isolate the n-alkanes from the fuel. Both carbon isotope ratio (δ(13)C) and hydrogen isotope ratio (δD) values for the n-alkanes were then determined by CSIA in each sample. The samples investigated had δ(13)C values that ranged from -30.1‰ to -26.8‰, whereas δD values ranged from -83‰ to -156‰. Plots of δD versus δ(13)C with sample n-alkane points connected in order of increasing carbon number gave well-separated clusters with characteristic shapes for each sample. Principal components analysis (PCA) with δ(13)C, δD, or combined δ(13)C and δD data was applied to extract the maximum information content. PCA scores plots could clearly differentiate the samples, thereby demonstrating the potential of this approach for distinguishing (e.g., fingerprinting) fuel samples using δ(13)C and δD values., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Colobines have been generally described as primates that use the anterior teeth minimally, but the posterior teeth extensively, to process leaves and related food items. However, variation among leaf monkeys in both anterior and posterior dental morphology has been recognized for decades. In this study, we turn to Hylander's (Science 189 (1975) 1095-1098) analysis of anterior incisor row length and Kay's (Adaptations for foraging in nonhuman primates, 1984) examination of relative molar crest length to test hypotheses proposed by them for Asian colobines. We present findings based on data from the largest Asian colobine sample measured to date. Our findings for incisor row length and molar cresting are not amenable to broad generalizations. In those instances when our morphological findings concur with those of Hylander (Science 189 (1975) 1095-1098) and Kay and Hylander (The ecology of arboreal folivores, 1978), the ecological evidence seldom supports the morphological predictions. The disassociation between diet and dental patterns may be a consequence of differential selection by fallback foods, anthropogenic disturbance or climatic shifts limiting preferred diets, or the use of food types as opposed to food mechanical properties for dietary categorization. We also found that in the case of both incisor row length and molar crest length, the patterns for males and females differed markedly. The reasons for these differences may in part be ascribed to the metabolic challenges faced by females and subsequent niche partitioning. We propose integrated analyses of the ingestive and digestive systems of our study taxa to clarify relationships among behavior, dental morphology, and diet in extant and extinct colobines., (Copyright © 2012 Wiley Periodicals, Inc.)

The global biomechanical impact of cranial sutures on the face and cranium during dynamic conditions is not well understood. It is hypothesized that sutures act as energy absorbers protecting skulls subjected to dynamic loads. This hypothesis predicts that sutures have a significant impact on global patterns of strain and cranial structural stiffness when analyzed using dynamic simulations; and that this global impact is influenced by suture material properties. In a finite element model developed from a juvenile Rhesus macaque cranium, five different sets of suture material properties for the zygomaticotemporal sutures were tested. The static and dynamic analyses produced similar results in terms of strain patterns and reaction forces, indicating that the zygomaticotemporal sutures have limited impact on global skull mechanics regardless of loading design. Contrary to the functional hypothesis tested in this study, the zygomaticotemporal sutures did not absorb significant amounts of energy during dynamic simulations regardless of loading speed. It is alternatively hypothesized that sutures are mechanically significant only insofar as they are weak points on the cranium that must be shielded from unduly high stresses so as not to disrupt vitally important growth processes. Thus, sutural and overall cranial form in some vertebrates may be optimized to minimize or otherwise modulate sutural stress and strain., (Copyright © 2011 Wiley Periodicals, Inc.)