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At the Interstices of Organizations: The Expansion of the Management Consulting Profession, 1933-97
No full textThis book describes and analyzes this worldwide flow of management ideas and the key carriers of these ideas
A Radiomics Machine Learning Model for Post-Radiotherapy Overall Survival Prediction of Non-Small Cell Lung Cancer (NSCLC)
No full textPurpose: To predict post-radiotherapy overall survival group of NSCLC patients based on clinical information and radiomics analysis of simulation CT.
Materials/Methods: A total of 258 non-adenocarcinoma patients who received radical
radiotherapy or chemo-radiation were studied: 45/50/163 patients were identified as
short(0-6mos)/mid(6-12mos)/long(12+mos) survival groups, respectively. For each
patient, we first extracted 76 radiomics features within the gross tumor volume(GTV)
identified in the simulation CT; these features were combined with patient clinical
information (age, overall stage, and GTV volume) as a patient-specific feature vector,
which was utilized by a 2-step machine learning model for survival group prediction.
This model first identifies patients with long survival prediction via a supervised binary
classifier; for those with otherwise prediction, a 2nd classifier further generates short/mid
survival prediction. Two machine learning classifiers, explainable boosting
machine(EBM) and balanced random forest(BRF), were interrogated as a comparison
study. During the model training, all patients were divided into training/test sets by an
8:2 ratio, and 100-fold random sampling were applied to the training set with a 7:1
validation ratio. Model performances were evaluated by the sensitivity, accuracy, and
ROC results.
Results: The model with EBM demonstrated an overall ROC AUC (0.58±0.04) with
limited sensitivities in short (0.02±0.04) and mid group (0.11±0.08) predictions due to
imbalanced data sample distribution. In contrast, the model with BRF improved
short/mid group sensitivities to 0.32±0.11/0.29±0.16, respectively, but the improvement
of ROC AUC (0.60±0.04) is limited. Nevertheless, both EBM (0.46±0.04) and BRF
(0.57±0.04) approaches achieved limited overall accuracy; a noticeable overlap was
found in their feature lists with top 10 feature weight rankings.
Conclusion: The proposed two-step machine learning model with BRF classifier
possesses a better performance than the one with EBM classifier in the post-radiotherapy
survival group prediction of NSCLC. Future works, preferably in the joint use of deep
learning, are in demand to further improve the prediction results.</p
Evaluation of antihypertensive drugs in combination with enzyme replacement therapy in mice with Pompe disease.
No full textPompe disease is caused by the deficiency of lysosomal acid α-glucosidase (GAA) leading to progressive myopathy. Enzyme replacement therapy (ERT) with recombinant human (rh) GAA has limitations, including inefficient uptake of rhGAA in skeletal muscle linked to low cation-independent mannose-6-phosphate receptor (CI-MPR) expression.PurposeTo test the hypothesis that antihypertensive agents causing muscle hypertrophy by increasing insulin-like growth factor 1 expression can increase CI-MPR-mediated uptake of recombinant enzyme with therapeutic effects in skeletal muscle.MethodsThree such agents were evaluated in mice with Pompe disease (carvedilol, losartan, and propranolol), either with or without concurrent ERT.ResultsCarvedilol, a selective β-blocker, increased muscle strength but reduced biochemical correction from ERT. Administration of drugs alone had minimal effect, with the exception of losartan that increased glycogen storage and mortality either by itself or in combination with ERT.ConclusionThe β-blocker carvedilol had beneficial effects during ERT in mice with Pompe disease, in comparison with propranolol or losartan. Caution is warranted when prescribing antihypertensive drugs in Pompe disease
Acute and chronic glutamate NMDA antagonist treatment attenuates dopamine D<sub>1</sub> antagonist-induced reduction of nicotine self-administration in female rats.
No full textMultiple interacting neural systems are involved in sustaining nicotine reinforcement. We and others have shown that dopamine D1 receptors and glutamate NMDA receptors both play important roles in nicotine reinforcement. Blockade of D1 receptors with the antagonist SCH-23390 (0.02 mg/kg) both acutely and chronically significantly decreased nicotine self-administration in rats. Blockade of NMDA receptors (10 mg/kg) acutely with memantine significantly increased nicotine self-administration, but chronic blockade of NMDA receptors with memantine significantly decreased nicotine self-administration. The current study examined the interactions of acute and chronic administration of SCH-23390 and memantine on nicotine self-administration in female rats. Replicating earlier studies, acute and chronic SCH-23390 significantly decreased nicotine self-administration and memantine had a biphasic effect with acute administration increasing nicotine self-administration and chronic memantine showed a non-significant trend toward decreasing it. However, chronic interaction study showed that memantine significantly attenuated the decrease in nicotine self-administration caused by chronic SCH-23390. These studies provide important information that memantine attenuates the efficacy of D1 antagonist SCH 23390 in reducing nicotine-self-administration. These two drugs do not appear to have mutually potentiating effects to aid tobacco cessation
Changes in thoracic kyphosis negatively impact sagittal alignment after lumbar pedicle subtraction osteotomy: a comprehensive radiographic analysis.
No full textStudy designConsecutive, multicenter retrospective review.ObjectiveTo evaluate if change in thoracic kyphosis (TK) has a positive or negative impact on spinopelvic alignment after lumbar pedicle subtraction osteotomy (PSO) with short fusions.Summary of background dataIn the setting of sagittal malalignment, the effect of large vertebral resections can now be anticipated in long fusions, but their impact on unfused segments (reciprocal changes [RC]) remains poorly understood.MethodsA total of 34 adult patients (mean age = 54 years; SD = 12) who underwent lumbar PSO with upper instrumented vertebra below T10 were included. Radiographic analysis included pre- and postassessment of TK, lumbar lordosis (LL), sagittal vertical axis (SVA), T1 spinopelvic inclination (T1SPI), pelvic tilt (PT), and pelvic incidence (PI). Final SVA and PT were analyzed to determine successful realignment. RC in the thoracic spine was designated favorable or unfavorable on the basis of impact on final SVA and PT.ResultsMean PSO resection was 26°. LL increased from 20° to 49° (P ConclusionSignificant postoperative alignment changes can occur through unfused thoracic spinal segments after lumbar PSO. Unfavorable RC may limit optimal correction and lead to clinical failures. Risk factors for unfavorable thoracic RC include older patients, larger preoperative PI and PT, and worse preoperative T1SPI and are not simply due to junctional failure. Care should be taken with selective lumbar fusion and PSO in older patients and in those with severe preoperative spinopelvic parameters
Access to COVID-19 testing by individuals with housing insecurity during the early days of the COVID-19 pandemic in the United States: a scoping review.
No full textIntroductionThe COVID-19 pandemic focused attention on healthcare disparities and inequities faced by individuals within marginalized and structurally disadvantaged groups in the United States. These individuals bore the heaviest burden across this pandemic as they faced increased risk of infection and difficulty in accessing testing and medical care. Individuals experiencing housing insecurity are a particularly vulnerable population given the additional barriers they face. In this scoping review, we identify some of the barriers this high-risk group experienced during the early days of the pandemic and assess novel solutions to overcome these barriers.MethodsA scoping review was performed following PRISMA-Sc guidelines looking for studies focusing on COVID-19 testing among individuals experiencing housing insecurity. Barriers as well as solutions to barriers were identified as applicable and summarized using qualitative methods, highlighting particular ways that proved effective in facilitating access to testing access and delivery.ResultsUltimately, 42 studies were included in the scoping review, with 143 barriers grouped into four categories: lack of cultural understanding, systemic racism, and stigma; medical care cost, insurance, and logistics; immigration policies, language, and fear of deportation; and other. Out of these 42 studies, 30 of these studies also suggested solutions to address them.ConclusionA paucity of studies have analyzed COVID-19 testing barriers among those experiencing housing insecurity, and this is even more pronounced in terms of solutions to address those barriers. Expanding resources and supporting investigators within this space is necessary to ensure equitable healthcare delivery
A Review of the Use of Early-Action Incentives in U.S. Environmental Markets
No full textEarly action can refer to activities undertaken prior to a regulatory program or the generation of a particular service before its use to mitigate an impact elsewhere. In U.S. environmental markets, early action can result in multiple benefits. One benefit is facilitation of market function by helping to generate a sufficient supply of viable, low-cost credits to buyers and gain momentum in new markets. Another benefit is providing advance mitigation, which can speed the delivery of ecosystem services. As markets emerge and mature, early action can help reduce lags in environmental performance, improve outcomes, and encourage innovation in mitigation approaches. Multiple tools have been proposed for encouraging early action in ecosystem services markets. To varying extents, these tools have also been deployed, providing valuable experience and insight into their functioning. This paper presents several case studies of how these tools have been used in wetland and stream mitigation, species and habitat banking, greenhouse gas emissions reduction and sequestration, and water quality trading. It finds that early action incentives necessary to motivate sellers differ from those necessary to motivate buyers and that interventions should account for this reality. The tool or approach best suited to encourage early action may also vary as conditions change and new barriers arise. Anecdotal evidence suggests the potential for benefits to accrue from early action, but additional data on the costs and benefits of early action are needed to inform the selection and implementation of specific tools. A revised version of the paper appears in the journal Land Use Policy