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Soil respiration is the sum of respiration processes in the soil and is a major flux in the global carbon cycle. It is usually assumed that the CO2 efflux is equal to the soil respiration rate. Here we challenge this assumption by combining measurements of CO2 with high-precision measurements of O2. These measurements were conducted on different ecosystems and soil types and included measurements of air samples taken from the soil profile of three Mediterranean sites: a temperate forest and two alpine forests. Rootfree soils from the alpine sites were also incubated in the lab. We found that the ratio between the CO2 efflux and the O2 influx (defined as apparent respiratory quotient, ARQ) was in the range of 0.14 to 1.23 and considerably deviated from the value of 0.9±0.1 expected from the elemental composition of average plants and soil organic matter. At the Mediterranean sites, these deviations are explained as a result of CO2 dissolution in the soil water and transformation to bicarbonate ions in these high-pH soils, as well as by carbonate mineral dissolution and precipitation processes. Thus, a correct estimate of the short-term, chamber-based biological respiratory flux in such soils can only be made by dividing the measured soil CO2 efflux by the average (efflux-weighted) soil profile ARQ. Applying this approach to a semiarid pine forest resulted in an estimated short-term biological respiration rate that is 3.8 times higher than the chamber-measured surface CO2. The ARQ values often observed in the more acidic soils were unexpectedly low (< 0.7). These values probably result from the oxidation of reduced iron, which has been formed previously during times of high soil moisture and local anaerobic conditions inside soil aggregates. The results reported here provide direct quantitative evidence of a large temporal decoupling between soil--gas exchange fluxes and biological soil respiration. [ABSTRACT FROM AUTHOR]

"The battle over the Pentagon's billions has traditionally been fought between two forces--those who want more new planes and ships and tanks, and those who want more money for troops. [...]

Soil respiration, is the sum of respiration processes in the soil, and is a major flux in the global carbon cycle. It is usually assumed that the CO2 efflux is equal to the soil respiration rate. Here we challenge this assumption by combining measurements of CO2 with high-precision measurements of O2. These measurements were conducted on different ecosystems and soil types, and included measurements of air-samples taken from the soil profile of three Mediterranean sites, a temperate forest, and two alpine forests. Root-free soils from the alpine sites were also incubated at the lab. We found that the ratio between the CO2 efflux to the O2 influx (which we defined as apparent respiratory quotient, ARQ) was in the range of 0.14 to 1.23, which strongly deviates from 0.9±0.1, which is the ratio expected from the elemental composition of average plants and soil organic matter. At the Mediterranean sites these deviations were explained as a result of CO2 dissolution in the soil water and transformation to bi-carbonate in these high pH soils, and by carbonates dissolution and precipitation processes. Thus, correct estimate of the short-term, chamber-based biological respiratory flux in such soils can only be made by dividing the measured CO2 efflux by the average (efflux weighted) soil profile ARQ. We demonstrated that applying this approach to a semiarid pine forest resulted in estimated short-term respiration rate 3.8 times higher than the chamber-measured surface CO2 efflux (8.8 µmol CO2 m-2 s-1 instead of 2.3 µmol CO2 m-2 s-1, at the time of measurement). The ARQ values that were often found for the more acidic soils were lower than 0.7, and hence surprising. These values might be the result of the oxidation of reduced iron, which could previously form during times of high soil moisture and local anaerobic conditions inside aggregates. Further research is needed to confirm that low ARQ found in non-calcareous soils, is the result of this process, which can cause additional temporal decoupling between gas fluxes and soil respiration. [ABSTRACT FROM AUTHOR]

The focal adhesion kinase (FAK) gene produces a tyrosine kinase that localises to contact points between cells and extracellular matrix. It is believed to be an important signal molecule in cell adhesion. We have isolated a human homologue of the FAK gene from primary sarcomas and looked for FAK mRNA in 49 human tissue samples, including paired normal and neoplastic samples. We found increased levels of FAK in 1 of 8 adenomatous tissues, in 17 of 20 invasive tumours, and in all 15 metastatic tumours. There was no detectable FAK mRNA in 6 normal tissue samples. These observations suggest that FAK overexpression may accompany changes in signal pathways involved in tumour cell invasion. [ABSTRACT FROM AUTHOR]

Background: Intracerebral hemorrhage (ICH) is a potential complication from traumatic brain injury, with a 30-day mortality rate of 35-52%. Rapid diagnosis allows for earlier treatment, which impacts patient outcomes. A trauma activation (TA) is called when injury severity meets institutional criteria. The patient is immediately roomed, and a multispecialty team is present. A trauma evaluation (TE) occurs when injuries are identified after standard triage processes., Objectives: Our aim was to determine whether TA patients with ICH were diagnosed and treated more rapidly than TE patients., Methods: This was a retrospective study of patients presenting to trauma centers within a large hospital system diagnosed with traumatic ICH between January 2018 and December 2018. Patients were categorized as TA or TE patients. The time to diagnosis was compared between groups, and additional times were evaluated, including time to imaging, computed tomography interpretation, and treatment., Results: A total of 294 patients were included. Groups had similar demographic characteristics and medical history; there was no difference in head Abbreviated Injury Score, Injury Severity Score, or anticoagulant use. Time to diagnosis was decreased for TA patients compared with TE patients (p < 0.0001). In addition, TA patients received treatment sooner (median 107 min) than TE patients (184.5 min) (p < 0.0001)., Conclusions: Diagnosis and treatment times were significantly faster in TA patients than in TE patients. Given the similarities in injury severity between groups, the increased time to treatment may be detrimental for patients. Trauma activations are a resource-heavy process, but TE delays care. These data suggest that an intermediary process may be beneficial., Competing Interests: Declaration of competing interest None., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The oxygen isotopes ratio (δ 18 O) of microbial cell water strongly controls the δ 18 O of cell phosphate and of other oxygen-carrying moieties. Recently it was suggested that the isotopic ratio in cell water is controlled by metabolic water, which is the water produced by cellular respiration. This potentially has important implications for paleoclimate reconstruction, and for measuring microbial carbon use efficiency with the 18 O-water method. Carbon use efficiency strongly controls soil organic matter preservation. Here, we directly tested the effect of metabolic water on microbial cells, by conducting experiments with varying the δ 18 O of headspace O 2 and the medium water, and by measuring the δ 18 O of cell phosphate. The latter is usually assumed to be in isotopic equilibrium with the cell's water. Our results showed no correlation between the δ 18 O of O 2 and that of the cell phosphate, contradicting the hypothesis that metabolic water is an important driver of δ 18 O of microbial cell water. However, our labeled 18 O water experiments indicated that only 43% of the oxygen in the cell's phosphate is derived from equilibration with the medium water, during late-log to early-stationary growing phase. This could be explained by the isotopic effects of intra-and extra-cellular hydrolysis of organic compounds containing phosphate., 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. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2023 Weiner, Tamburini, Keren, Keinan and Angert.)

Aseptic loosening is a considerable complication that affects the longevity of total knee arthroplasty (TKA) implants. Surgeon technique may help minimize aseptic loosening after TKA. Meticulous cementation of the prosthesis and the bone surface during various stages of cement polymerization will maximize cement adherence to the prosthesis and the bone, respectively. Pressurization of the cement in the canal and at the cut surface to achieve at least 2 mm of cement depth penetration has been reported to increase TKA implant longevity., (Copyright © 2021 by the American Academy of Orthopaedic Surgeons.)

Objectives: This qualitative investigation sought to identify the motivational factors that contribute to drowsy driving in college students and to discover important messaging strategies that may help prevent or reduce this behavior in this population., Design: Four focus groups of college students., Setting: A large university in the Washington, DC, metropolitan area during the Fall 2016 term., Participants: Twenty-six undergraduate students between the ages of 18 and 25 years., Measurements: Notes and transcripts from the focus group sessions were analyzed to identify recurring themes regarding attitudes, motivations, experiences, influences, and potential preventive messaging strategies related to drowsy driving., Results: Although most participants had heard of drowsy driving and were concerned about it, they did not associate it with legal risks and were more concerned about alcohol-impaired and distracted driving as crash risks. Participants viewed drowsy driving as a normal and unavoidable part of their lives over which they had little control. For potential anti-drowsy driving messaging strategies, participants preferred messages delivered via audiovisual or social media that featured graphic and emotional portrayals of crashes and their consequences. Participants also voiced strong support for preventive messaging strategies equating various degrees of sleep deprivation to known impairing levels of alcohol, as well as messages providing cues to action to actual drowsy drivers on roadways., Conclusions: Increased enforcement, education, and public messaging campaigns are needed to increase knowledge and influence attitudes and opinions among young drivers about the dangers and social unacceptability of drowsy driving., (Copyright © 2018 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.)

The role of preoperative bowel prep in the pediatric surgical population is uncertain. We performed a randomized prospective study to evaluate noninferiority between the presence or absence of a preoperative bowel prep in elective pediatric bowel surgery on postoperative outcomes. Patients aged three months to 18 years were recruited and randomized to the bowel prep group or the no bowel prep group. Patients were evaluated in-hospital and at postoperative clinic visits. Thirty-two patients were recruited; 18 in the bowel prep group and 14 in the no bowel prep group. There was no statistical difference (P > 0.05) in complications between the groups. Complications were observed in five patients in each group (27.8% and 35.7%, respectively). In the bowel prep group, two (11.1%) had wound infection (vs three, 21.4%), 0 had an intra-abdominal abscess (vs one, 7.1%), one (5.6%) had sepsis (vs one, 7.1%), one (5.6%) had an anastomotic leak (vs 0), and three (16.7%) had a bowel obstruction (vs one, 7.1%). There were no extra-abdominal complications. There were no significant differences in complications between the two groups. Further research is warranted, but may require a multi-institutional trial to recruit sufficient numbers to make conclusions about the significance of the need for bowel prep.

The stable oxygen isotope compositions of soil phosphate (δ(18)O(p)) were suggested recently to be a tracer of phosphorus cycling in soils and plants. Here we present a survey of bioavailable (resin-extractable or resin-P) inorganic phosphate δ(18)O(p) across natural and experimental rainfall gradients, and across soil formed on sedimentary and igneous bedrock. In addition, we analyzed the soil HCl-extractable inorganic δ(18)O(p), which mainly represents calcium-bound inorganic phosphate. The resin-P values were in the range 14.5-21.2‰. A similar range, 15.6-21.3‰, was found for the HCl-extractable inorganic δ(18)O(p), with the exception of samples from a soil of igneous origin that show lower values, 8.2-10.9‰, which indicate that a large fraction of the inorganic phosphate in this soil is still in the form of a primary mineral. The available-P δ(18)O(p) values are considerably higher than the values we calculated for extracellular hydrolysis of organic phosphate, based on the known fractionation from lab experiments. However, these values are close to the values expected for enzymatic-mediated phosphate equilibration with soil-water. The possible processes that can explain this observation are (1) extracellular equilibration of the inorganic phosphate in the soil; (2) fractionations in the soil are different than the ones measured at the lab; (3) effect of fractionation during uptake; and (4) a flux of intercellular-equilibrated inorganic phosphate from the soil microbiota, which is considerably larger than the flux of hydrolyzed organic-P.

Self-management of mental illness is a therapeutic paradigm that draws on a distinctly biomedical conceptualization of the isolability of personhood from pathology. This discourse posits a stable and rational patient/consumer who can observe, anticipate, and preside over his disease through a set of learned practices. But in the case of bipolar disorder, where the rationality of the patient is called into question, the managing self is elusive, and the disease that is managed coincides with the self. While humanist critiques of the biomedical model as applied to mental illness have argued that its logic fatalistically denies patients intentionality and effectiveness (Luhrmann, Of Two Minds: The Growing Disorder in American Psychiatry, 2000), biomedical proponents claim that psychiatry's way of envisioning the body as under the control of the intentional mind actually returns agency to the patient/consumer. Rose (The Psychiatric Gaze, 1999) remarks that biomedical models have the potential to "[open] that which was considered natural to a form of choice" (p. 37), and that techniques of medical self-control help constitute the free embodied liberal subject who is obliged to calculate and choose. Through an examination of clinical literature as well as the practices and narratives of members of a bipolar support group, this paper explores ethnographically the possibilities for subjectivity and agency that are conditioned or foreclosed by the self-management paradigm, which seems to simultaneously confer and deny rational selfhood to bipolar patients. To express their expertise as rational self-managers, patients/consumers must, paradoxically, articulate constant suspicion toward their present thoughts and emotions, and distrust of an imagined future self. I argue that through their self-management practices, bipolar support group members model provisional and distributed forms of agency based on an elusive, discontinuous, and only partially knowable or controllable self-revealing, perhaps, the limits of the contemporary reification and medicalization of both selfhood and disease.

Objective: To determine whether implementation of a collaborative, evidence-based algorithm for care of pediatric parapneumonic effusion and empyema (PPE) can improve the quality of care delivered., Study Design: Prospective cohort with retrospective control comparison of children aged 1 month to 18 years admitted with a clinical diagnosis of PPE. Quality improvement techniques were used to develop an algorithm, which was implemented September 2008. Primary outcome measures were decreased median and variability in length of stay (LOS), reduction in the use of chest computed tomography (CT), reduction in the total number of painful procedures, and increased initial use of effective drainage procedures when drainage was indicated., Results: Compared with controls, algorithm implementation substantially reduced use of chest CT (0% vs. 41% of patients, P = 0.01) with no observed negative impact on LOS. Reductions in median LOS were not significant, but variability in LOS was reduced (P < 0.01 by F-test). Changes in number of procedures and use of effective drainage when indicated were in the predicted direction but not statistically significant., Conclusions: Quality improvement techniques are an effective means for incorporating evidence-based medicine into pediatric care. PPE can be managed safely without the use of chest CT., (Copyright © 2011 Wiley-Liss, Inc.)