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1.
PLoS One ; 19(7): e0305334, 2024.
Article in English | MEDLINE | ID: mdl-39024366

ABSTRACT

Warehousing and storage is an economically vital industry, with 1.2 million workers in 2020. The Fulfillment Center Intervention Study focuses on workers in fulfillment centers in the e-commerce segment of this industry. Fulfillment centers are a growing yet understudied work environment which provides a unique setting to further examine how working conditions and worker voice influence health. The Study involves a group-randomized controlled trial comparing participants in worksites randomized to launch the participatory intervention (Health and Well-Being Committees, or HaWCs) with participants working for the same firm in control sites. HaWCs serve as a new formal voice channel where a small group of frontline workers and supervisors solicit workers' concerns and ideas about safety (e.g., physical hazards), the psychosocial environment (e.g., how workers feel about their treatment at work), and work organization (e.g., workflow, training opportunities, scheduling) and then develop and implement improvement projects in response. The primary objectives of the study are to evaluate the efficacy of the HaWC intervention and its effect on mental health outcomes and changes in the conditions of work within fulfillment centers, and to conduct a process evaluation of key contextual factors that support effective intervention implementation and sustained engagement. To our knowledge, this will be the first trial of a participatory intervention within a fulfillment center setting. Anticipated challenges include competing demands and company initiatives that may limit management support and high turnover. Should the intervention be shown to be feasible, the outcomes from this study will inform future randomized controlled trials of participatory interventions. Trial registration: This trial is registered with the ClinicalTrials.gov registry (NCT05199415) and approved by the Institutional Review Board (IRB) at the Massachusetts Institute of Technology (Protocol: 200800024).


Subject(s)
Occupational Health , Workplace , Humans , Workplace/psychology , Male , Female
2.
Sci Rep ; 14(1): 13806, 2024 06 14.
Article in English | MEDLINE | ID: mdl-38877077

ABSTRACT

Antenatal anxiety is among the risk factors for adverse birth outcomes, which are common in Pakistan. Between 2019 and 2022, we conducted a randomized controlled trial to evaluate the effects of the Happy Mother-Healthy Baby program, designed to reduce anxiety during pregnancy through use of Cognitive Behavior Therapy, on birth outcomes with 796 women in Rwalpindi, Pakistan. We performed intent-to-treat analysis and per protocol analyses. Intention-to-treat analyses showed no difference in the odds of low birthweight (LBW) (Adj. OR = 0.82, 95% CI 0.55-1.28 p = 0.37), preterm birth (PTB) (Adj. OR = 1.20 95% CI 0.83-1.71, p = 0.33) or small-for-gestational age (SGA) birth, (Adj. OR = 0.76, 95% CI 0.56-1.09, p = 0.16). Among completers who received ≥ 5 intervention sessions, the odds of LBW and SGA were 39% and 32% lower (Adj. OR = 0.61, 95% CI 0.43-0.87, p < 0.01; Adj. OR = 0.68, 95% CI 0.53-0.89, p < 0.01). The significant LBW and SGA results among the intervention completers suggest that the program may be effective when a sufficient dose is received. However, confirmation of these findings is needed due to the fact that randomization is not maintained in completer analyses.Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT03880032, 19/03/2019.


Subject(s)
Anxiety , Cognitive Behavioral Therapy , Humans , Female , Pregnancy , Pakistan/epidemiology , Cognitive Behavioral Therapy/methods , Adult , Anxiety/therapy , Infant, Newborn , Infant, Low Birth Weight , Premature Birth/prevention & control , Pregnancy Complications/therapy , Pregnancy Complications/psychology , Pregnancy Outcome , Infant, Small for Gestational Age , Young Adult , Prenatal Care/methods
3.
J Geophys Res Planets ; 126(2): e2020JE006530, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33777606

ABSTRACT

In the Late Noachian to Early Hesperian period, rivers transported detritus from igneous source terrains to a downstream lake within Gale crater, creating a stratified stack of fluviolacustrine rocks that is currently exposed along the slopes of Mount Sharp. Controversy exists regarding the paleoclimate that supported overland flow of liquid water at Gale crater, in large part because little is known about how chemical and mineralogical paleoclimate indicators from mafic-rock dominated source-to-sink systems are translated into the rock record. Here, we compile data from basaltic terrains with varying climates on Earth in order to provide a reference frame for the conditions that may have prevailed during the formation of the sedimentary strata in Gale crater, particularly focusing on the Sheepbed and Pahrump Hills members. We calculate the chemical index of alteration for weathering profiles and fluvial sediments to better constrain the relationship between climate and chemical weathering in mafic terrains, a method that best estimates the cooler limit of climate conditions averaged over time. We also compare X-ray diffraction patterns and mineral abundances from fluvial sediments in varying terrestrial climates and martian mudstones to better understand the influence of climate on secondary mineral assemblages in basaltic terrains. We show that the geochemistry and mineralogy of most of the fine-grained sedimentary rocks in Gale crater display first-order similarities with sediments generated in climates that resemble those of present-day Iceland, while other parts of the stratigraphy indicate even colder baseline climate conditions. None of the lithologies examined at Gale crater resemble fluvial sediments or weathering profiles from warm (temperate to tropical) terrestrial climates.

4.
Geosphere (Boulder) ; 16(6): 1508-1537, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-33304202

ABSTRACT

Extraformational sediment recycling (old sedimentary rock to new sedimentary rock) is a fundamental aspect of Earth's geological record; tectonism exposes sedimentary rock, whereupon it is weathered and eroded to form new sediment that later becomes lithified. On Mars, tectonism has been minor, but two decades of orbiter instrument-based studies show that some sedimentary rocks previously buried to depths of kilometers have been exposed, by erosion, at the surface. Four locations in Gale crater, explored using the National Aeronautics and Space Administration's Curiosity rover, exhibit sedimentary lithoclasts in sedimentary rock: At Marias Pass, they are mudstone fragments in sandstone derived from strata below an erosional unconformity; at Bimbe, they are pebble-sized sandstone and, possibly, laminated, intraclast-bearing, chemical (calcium sulfate) sediment fragments in conglomerates; at Cooperstown, they are pebble-sized fragments of sandstone within coarse sandstone; at Dingo Gap, they are cobble-sized, stratified sandstone fragments in conglomerate derived from an immediately underlying sandstone. Mars orbiter images show lithified sediment fans at the termini of canyons that incise sedimentary rock in Gale crater; these, too, consist of recycled, extraformational sediment. The recycled sediments in Gale crater are compositionally immature, indicating the dominance of physical weathering processes during the second known cycle. The observations at Marias Pass indicate that sediment eroded and removed from craters such as Gale crater during the Martian Hesperian Period could have been recycled to form new rock elsewhere. Our results permit prediction that lithified deltaic sediments at the Perseverance (landing in 2021) and Rosalind Franklin (landing in 2023) rover field sites could contain extraformational recycled sediment.

5.
Proc Natl Acad Sci U S A ; 114(9): 2166-2170, 2017 02 28.
Article in English | MEDLINE | ID: mdl-28167765

ABSTRACT

Carbon dioxide is an essential atmospheric component in martian climate models that attempt to reconcile a faint young sun with planetwide evidence of liquid water in the Noachian and Early Hesperian. In this study, we use mineral and contextual sedimentary environmental data measured by the Mars Science Laboratory (MSL) Rover Curiosity to estimate the atmospheric partial pressure of CO2 (PCO2) coinciding with a long-lived lake system in Gale Crater at ∼3.5 Ga. A reaction-transport model that simulates mineralogy observed within the Sheepbed member at Yellowknife Bay (YKB), by coupling mineral equilibria with carbonate precipitation kinetics and rates of sedimentation, indicates atmospheric PCO2 levels in the 10s mbar range. At such low PCO2 levels, existing climate models are unable to warm Hesperian Mars anywhere near the freezing point of water, and other gases are required to raise atmospheric pressure to prevent lake waters from being lost to the atmosphere. Thus, either lacustrine features of Gale formed in a cold environment by a mechanism yet to be determined, or the climate models still lack an essential component that would serve to elevate surface temperatures, at least locally, on Hesperian Mars. Our results also impose restrictions on the potential role of atmospheric CO2 in inferred warmer conditions and valley network formation of the late Noachian.

6.
Science ; 329(5990): 421-4, 2010 Jul 23.
Article in English | MEDLINE | ID: mdl-20522738

ABSTRACT

Decades of speculation about a warmer, wetter Mars climate in the planet's first billion years postulate a denser CO2-rich atmosphere than at present. Such an atmosphere should have led to the formation of outcrops rich in carbonate minerals, for which evidence has been sparse. Using the Mars Exploration Rover Spirit, we have now identified outcrops rich in magnesium-iron carbonate (16 to 34 weight percent) in the Columbia Hills of Gusev crater. Its composition approximates the average composition of the carbonate globules in martian meteorite ALH 84001. The Gusev carbonate probably precipitated from carbonate-bearing solutions under hydrothermal conditions at near-neutral pH in association with volcanic activity during the Noachian era.


Subject(s)
Carbonates , Mars , Water , Atmosphere , Carbon Dioxide , Carbonates/chemistry , Climate , Extraterrestrial Environment , Ferrous Compounds , Magnesium , Meteoroids , Spacecraft , Temperature
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