Category: Statistics

Proc Natl Acad Sci U S A. 2024 Jan 2;121(1):e2302480120. doi: 10.1073/pnas.2302480120. Epub 2023 Dec 26.

ABSTRACT

Arid and semi-arid regions of the world are particularly vulnerable to greenhouse gas-driven hydroclimate change. Climate models are our primary tool for projecting the future hydroclimate that society in these regions must adapt to, but here, we present a concerning discrepancy between observed and model-based historical hydroclimate trends. Over the arid/semi-arid regions of the world, the predominant signal in all model simulations is an increase in atmospheric water vapor, on average, over the last four decades, in association with the increased water vapor-holding capacity of a warmer atmosphere. In observations, this increase in atmospheric water vapor has not happened, suggesting that the availability of moisture to satisfy the increased atmospheric demand is lower in reality than in models in arid/semi-arid regions. This discrepancy is most clear in locations that are arid/semi-arid year round, but it is also apparent in more humid regions during the most arid months of the year. It indicates a major gap in our understanding and modeling capabilities which could have severe implications for hydroclimate projections, including fire hazard, moving forward.

PMID:38147646 | DOI:10.1073/pnas.2302480120

Proc Natl Acad Sci U S A. 2024 Jan 2;121(1):e2311280120. doi: 10.1073/pnas.2311280120. Epub 2023 Dec 26.

ABSTRACT

The dominant paradigm is that large tracts of Southeast Asia’s lowland rainforests were replaced with a “savanna corridor” during the cooler, more seasonal climates of the Last Glacial Maximum (LGM) (23,000 to 19,000 y ago). This interpretation has implications for understanding the resilience of Asia’s tropical forests to projected climate change, implying a vulnerability to “savannization”. A savanna corridor is also an important foundation for archaeological interpretations of how humans moved through and settled insular Southeast Asia and Australia. Yet an up-to-date, multiproxy, and empirical examination of the palaeoecological evidence for this corridor is lacking. We conducted qualitative and statistical analyses of 59 palaeoecological records across Southeast Asia to test the evidence for LGM savannization and clarify the relationships between methods, biogeography, and ecological change in the region from the start of Late Glacial Period (119,000 y ago) to the present. The pollen records typically show montane forest persistence during the LGM, while δ¹³C biomarker proxies indicate the expansion of C₄-rich grasslands. We reconcile this discrepancy by hypothesizing the expansion of montane forest in the uplands and replacement of rainforest with seasonally dry tropical forest in the lowlands. We also find that smooth forest transitions between 34,000 and 2,000 y ago point to the capacity of Southeast Asia’s ecosystems both to resist and recover from climate stressors, suggesting resilience to savannization. Finally, the timing of ecological change observed in our combined datasets indicates an ‘early’ onset of the LGM in Southeast Asia from ~30,000 y ago.

PMID:38147645 | DOI:10.1073/pnas.2311280120

Health Phys. 2024 Feb 1;126(2):65-78. doi: 10.1097/HP.0000000000001764.

ABSTRACT

The former Lamprecht uranium mine facility in Texas ceased operations well before the new millennium. However, decommissioning activities were never completed by the licensee. Consequently, a legal proceeding was authorized between state and licensee representatives. Meanwhile, state funds were used to hire an independent contractor to perform radiological surveys and assess the magnitude of residual radioactivity across the terrain at the site. The purpose of this study was to apply advanced spatial statistical methods to the survey data measured by contractors at the Lamprecht site to precisely predict remaining radioactive hotspot locations post soil remediation activities. To accomplish this, descriptive statistics such as Google maps and boxplots along with inferential spatial statistical techniques, e.g., kriging and semivariograms, were employed. R coding was also used throughout. Specifically, the descriptive statistical methods included geographical mapping of targeted areas at the site coupled with summary statistics. Inferentially, spatial analytical techniques were employed to pinpoint the locations of elevated radiation levels above regulatory limits. Our results suggest that fewer hotspots were identified after remediation activities were completed at the site. This study provides an additional analytical resource for the State of Texas regarding the release of this former in situ leach uranium mine site to landowners for unrestricted use.

PMID:38147633 | DOI:10.1097/HP.0000000000001764

J Gastrointestin Liver Dis. 2023 Dec 22;32(4):479-487. doi: 10.15403/jgld-4997.

ABSTRACT

AIMS: To assess the value of using integrated parametric ultrasound software for contrast-enhanced ultrasonography (CEUS) of liver tumors.

METHODS: 107 patients with liver tumors were studied. CEUS were performed to detect focal lesions. Parametric images were based on continuous CINE LOOPs, from the early-arterial phase (15 s) to the portal-venous phase (1 min) generated by perfusion software. The evaluations of the parametric images and their dignity for liver lesions were performed independently by an experienced and a less-experienced investigator. Computed tomography, magnetic resonance imaging scans or histological analysis were used as references.

RESULTS: High parametric image quality were obtained in all patients. Among the patients, 44% lesions were benign, 56% were malignant. The experienced investigator correctly classified 46 of 47 (98%) as benign, and 60 of 60 (100%) as malignant tumors based on the parametric images. The less-experienced investigator correctly classified 39 of 47 (83%) as benign, and 49 of 60 (82%) malignant tumors, acheaving a high statistical accuracy of 98% with this type of diagnostic.

CONCLUSION: Parametric imaging for grading the malignant degree of tumor may be a good complement to existing ultrasound techniques and was particularly helpful for improving the assessments of the less-experienced examiner.

PMID:38147619 | DOI:10.15403/jgld-4997

J Gastrointestin Liver Dis. 2023 Dec 22;32(4):438-443. doi: 10.15403/jgld-4932.

ABSTRACT

BACKGROUND AND AIMS: Fecal calprotectin (FC) is a biomarker of gut inflammation, and Escherichia coli Nissle 1917 (EcN) is a probiotic strain able to reduce gut inflammation and maintain disease remission in patients with inflammatory bowel disease (IBD). The aim is to assess the effects of EcN administration in patients with IBD in clinical remission and altered FC values.

METHODS: We prospectively included 82 patients with ulcerative colitis (UC) (n=49) and Crohn’s disease (CD) (n=33) in clinical remission and with FC values above 250 mcg/g (T0) who were treated with EcN alone for 2 months. FC values were assessed at the end of EcN treatment (T1) and clinical disease activity at 3 months (T2).

RESULTS: At T1 median FC values were significantly lower compared to T0 both in patients with CD (312 mcg/g vs 626 mcg/g, p<0.0001) and UC (100 mcg/g vs 584 mcg/g; p<0.0001). Patients with UC who experienced disease relapse at T2 had lesser reduction in median FC values at T1 (-229 mcg/g, vs -397 mcg/g, p=0.049), while in patients with CD we observed no statistically significant difference (-358 mcg/g, vs -427; p=0.568). In patients with UC, a reduction of at least 532 mcg/g in FC had an accuracy of 69.7% and a positive predictive value of 65.7% in predicting maintenance of remission.

CONCLUSIONS: A short course of EcN was associated with a reduction of FC values in patients with IBD in clinical remission and baseline altered FC values, and in patients with UC this decrease was associated with maintenance of clinical remission.

PMID:38147604 | DOI:10.15403/jgld-4932

Genetics. 2023 Dec 26:iyad218. doi: 10.1093/genetics/iyad218. Online ahead of print.

ABSTRACT

Inversions restrict recombination when heterozygous with standard arrangements, but often have few noticeable phenotypic effects. Nevertheless, there are several examples of inversions that can be maintained polymorphic by strong selection under laboratory conditions. A long-standing model for the source of such selection is divergence between arrangements with respect to recessive or partially recessive deleterious mutations, resulting in a selective advantage to heterokaryotypic individuals over homokaryotypes. This paper uses a combination of analytical and numerical methods to investigate this model, for the simple case of an autosomal inversion with multiple independent nucleotide sites subject to mildly deleterious mutations. A complete lack of recombination in heterokaryotypes is assumed, as well as constancy of the frequency of the inversion over space and time. It is shown that a significantly higher mutational load will develop for the less frequent arrangement. A selective advantage to heterokaryotypes is only expected when the two alternative arrangements are nearly equal in frequency, so that their mutational loads are very similar in size. The effects of some Drosophila pseudoobscura polymorphic inversions on fitness traits seem to be too large to be explained by this process, although it may contribute to some of the observed effects. Several population genomic statistics can provide evidence for signatures of a reduced efficacy of selection associated with the rarer of two arrangements, but there is currently little published data that are relevant to the theoretical predictions.

PMID:38147527 | DOI:10.1093/genetics/iyad218

Eur J Cardiovasc Nurs. 2023 Dec 26:zvad138. doi: 10.1093/eurjcn/zvad138. Online ahead of print.

ABSTRACT

AIM: Shared decision-making is recommended for patients considering treatment options for severe aortic stenosis (AS) and chronic coronary artery disease (CAD). This review aims to systematically identify and assess patient decision aids (PtDAs) for chronic CAD and AS and evaluate the international evidence on their effectiveness for improving the quality of decision-making.

METHODS AND RESULTS: Five databases (Cochrane, CINAHL, Embase, MEDLINE, PsycInfo), clinical trial registers and 30 PtDA repositories/websites were searched from 2006 to March 2023. Screening, data extraction and quality assessments were completed independently by multiple reviewers. Meta-analyses were conducted using Stata statistical software. Eleven AS and 10 CAD PtDAs were identified; seven were less than five years old. Over half the PtDAs were web-based and the remainder paper-based. One AS and two CAD PtDAs fully/partially achieved international PtDA quality criteria. Ten studies were included in the review; four reported on the development/evaluation of AS PtDAs and six on CAD PtDAs. Most studies were conducted in the USA with White, well-educated, English-speaking participants. No studies fulfilled all quality criteria for reporting PtDA development and evaluation. Meta-analyses found that PtDAs significantly increased patient knowledge compared to ‘usual care’ (mean difference:0.620; 95%CI 0.396, 0.845, p < 0.001) but did not change decisional conflict.

CONCLUSION: Patients who use PtDAs when considering treatments for AS or chronic CAD are likely to be better informed than those who do not. Existing PtDAs may not meet the needs of people with low health literacy levels as they are rarely involved in their development.

PMID:38147507 | DOI:10.1093/eurjcn/zvad138

Orthopedics. 2023 Dec 28:1-7. doi: 10.3928/01477447-20231220-05. Online ahead of print.

ABSTRACT

OBJECTIVE: This study sought to understand trends in industry payments for research awarded to orthopedic surgeons.

MATERIALS AND METHODS: The Centers for Medicare & Medicaid Services Open Payments database was queried for the years 2016 to 2021 for industry payments for research. Financial analyses were performed to understand temporal trends and differences by orthopedic subspecialty and principal investigator characteristics such as sex. The threshold for statistical significance was set at .05.

RESULTS: A total of 2014 orthopedic surgeons were identified, among whom 542 adult reconstruction (27%) and 460 sports medicine (23%) surgeons were major beneficiaries. Seventy-one female orthopedic surgeons comprised the minority (4%). Total research payments awarded during the study period aggregated to $266,633,592, with adult reconstruction ($88,819,047; 33%) and sports medicine ($57,949,822; 22%) receiving the highest amounts. Total research payments awarded trended upward yearly except for a decline in 2020 that subsequently rebounded (P<.001). Median annual research payment per orthopedic surgeon was $13,375. Median total industry payments per orthopedic surgeon differed between specialties (P <.001), with the highest amounts for adult reconstruction ($44,063) and sports medicine ($34,567) and the lowest amounts for hand ($12,052) and foot and ankle ($19,233). Median total payments did not differ significantly when stratified by sex (P=.276) and region (P=.906). Specialties in which the respective top three companies offered the majority of the research funding were musculoskeletal oncology (90%), pediatric orthopedics (66%), and shoulder and elbow (64%).

CONCLUSION: These results can be used as a primer for orthopedic surgeons seeking to leverage industry relationships to fund translational research. [Orthopedics. 202x;4x(x):xx-xx.].

PMID:38147497 | DOI:10.3928/01477447-20231220-05

Orthopedics. 2023 Dec 28:1-4. doi: 10.3928/01477447-20231220-03. Online ahead of print.

ABSTRACT

OBJECTIVE: Treating high-level athletes involves a balance between early and safe return to play. Various types of protective immobilization have been recommended after operatively treated Bennett’s fracture. The purpose of this study was to investigate if hand-based immobilization offers protection equivalent to forearm-based immobilization.

MATERIALS AND METHODS: A cadaveric model of Bennett’s fracture was created in 8 fresh-frozen, cadaveric forearms. Osteosynthesis was performed using a single headless compression screw. Three matched pairs were casted in either hand-based or forearm length, thumb spica casts, while 2 specimens remained un-casted as controls. Specimens were mounted on a custom testing apparatus. Weights were added in 6.8-kg increments until fixation failed and the fracture displaced. Fluoroscopy was performed after each trial. We used the Kruskal-Wallis non-parametric test to compare the groups. We considered P<.05 statistically significant.

RESULTS: Failure of fixation occurred at 6.8 kg in the control specimens. Fixation failed in hand-based and forearm length casts at a mean of 18.1±5.1 kg. We did not find a statistically significant difference between median values of load at failure in kilograms across control specimens and 2 immobilization categories (P=.114). All specimens in the hand-based group sustained additional wrist injuries, while no additional injuries were noted in the forearm length group.

CONCLUSION: Our study results showed that hand-based immobilization provides equivalent protection against fixation failure for operatively treated Bennett’s fractures but may predispose athletes to increased risk of wrist injury compared with traditional, forearm-based casting. [Orthopedics. 202x;4x(x):xx-xx.].

PMID:38147495 | DOI:10.3928/01477447-20231220-03

J Eur Acad Dermatol Venereol. 2023 Dec 26. doi: 10.1111/jdv.19770. Online ahead of print.

ABSTRACT

BACKGROUND: Hidradenitis suppurativa (HS) is a disease with an unmet need for treatment.

OBJECTIVE: To examine tolerability, safety and efficacy of oral phosphodiesterase-4 (PDE4) inhibitior orismilast 10-40 mg twice daily (BID) in HS.

METHODS: A Phase 2a, single-arm, single-centre, open-label, 16-week trial in HS patients. Adjustments in maximal dose and titration were allowed, to improve tolerability, dividing the study population in two groups who completed and discontinued 16 weeks of treatment. Descriptive statistics were applied to efficacy data from patients who completed treatment and patients who discontinued treatment prematurely. A last-observation-carried-forward (LOCF) approach was used for patients who discontinued treatment. The primary endpoint was percent change in the total number of abscesses and nodules (AN-count) at Week 16, with the HS Clinical Response with a 50% reduction in the AN-count (HiSCR50) as key secondary endpoint.

RESULTS: Of the 20 patients included, 9 completed 16 weeks of treatment and 11 discontinued treatment prematurely. The mean AN-count was reduced with 33.1% in patients who completed treatment and with 12.0% in patients who discontinued. HiSCR50 was achieved by 67.0% and 27.0% of patients who completed and discontinued treatment, respectively. Most adverse events were mild to moderate.

CONCLUSIONS: Oral orismilast demonstrated a dose-dependent tolerability, with mild to moderate adverse effects. Further, the results of this exploratory trial indicate that orismilast may lead to clinical improvements in HS. However, larger trials with tolerable dose ranges are warranted. The Trial is registered at Clinicaltrials.gov (UNI50007201) and EudraCT.ema.europa.eu (2021-000049-42).

PMID:38147438 | DOI:10.1111/jdv.19770