Condition indices for rigid pavements: A comparative analysis of state DOTs using Michigan PMS data

Pavement infrastructure is vital in providing services and links between various sectors of society. Therefore, thepreservation and maintenance of these roads are critical to attaining a pavement network in good conditionthroughout its service life. Various performance indicators like the international roughness index (IRI), pavementcondition index (PCI), and present serviceability rating (PSR) have been used by the state department of transportation (DOT) and highway agencies for evaluating pavement surface conditions and planning future maintenance strategies. Limited data availability, multiple distresses depending on region, lack of correlation of thesecondition indices to maintenance strategies, and data collection limitations pose a challenge for applying theseindices to local conditions. This paper compares condition indices of different states for rigid pavements. Further,using a specific condition index for local conditions is also highlighted. For this purpose, five states and theircorresponding condition indices were evaluated and compared to the Michigan DOT distress index (DI). Thesestates include Virginia, Minnesota, North Dakota, Louisiana, and Oregon. The corresponding distresses of eachcondition index were converted to make them compatible with the MDOT DI. This study used the MDOT'spavement management system (PMS) database to evaluate each condition index for 433 rigid pavement sections.Each distress index was plotted against MDOT DI and compared using a paired t-test. Results show that thecondition indices of Virginia and Minnesota are comparable to DI in terms of the Spearman correlation value. Thet-test results show that except for Virgina, condition indices from other states statistically differ from DI.Therefore, one can't use those directly for local conditions in Michigan. This paper presents the evaluation anddata requirements for each condition index and its impact on selecting a maintenance treatment.

Mechanical properties of Michigan Basin’s gypsum before and after saturation

The stability analysis of an abandoned underground gypsum mine requires the determination of the mine pillar’s strength.This is especially important for flooded abandoned mines where the gypsum pillars become saturated and are subjected to dissolution after flooding.Further,mine pillars are subjected to blast vibrations that generate some level of macro- and micro-fracturing.Testing samples of gypsum must,therefore,simulate these conditions as close as possible.In this research,the strength of gypsum is investigated in an as-received saturated condition using uniaxial compressive strength (UCS),Brazilian tensile strength (BTS) and point load index (PLI) tests.The scale effect was investigated and new correlations were derived to describe the effect of sample size on both UCS and BTS under dry and saturated conditions.Effects of blasting on these parameters were observed and the importance of choosing the proper samples was discussed.Finally,correlations were derived for both compressive and tensile strengths under dry and saturated conditions from the PLI test results,which are commonly used as a simple substitute for the indirect determination of UCS and BTS.

Distribution of Sediment Measurements in Lake Michigan as a Case Study: Implications for Estimating Sediment and Water Interactions in Eutrophication and Bioaccumulation Models

Lake Michigan, the sixth largest freshwater lake in the world by surface area, was utilized as a water body for assessment. Field data collected at sampling sites throughout the lake in an intensive monitoring effort were utilized for evaluation of the distribution of sediment measurements. An assessment of sediment nutrient and carbon measurements within Lake Michigan was completed to recognize strata resulting from the hydrodynamics of the system. Nonparametric comparison tests revealed that significant differences exist between measurements of sediment nutrients and organic carbon in the lake using strata based upon water column depth (all results demon-strated a p < 0.05, α = 0.05). Cross-validation analysis was applied to the field-collected samples, revealing that large errors occur when estimating sediment flux of carbon or nutrients at a given location in the lake without considering stratification of the distributions of these measurements. Errors in estimating sediment concentrations of nutrients and carbon specific to a location in the lake demonstrated a statistically significant increase when stratification of sediment measurements wasn’t employed among sites. For example, distributions of errors in estimating all nutrients and organic carbon concentrations, whereby distance squared inverse interpolation methods were applied, demonstrated a statistically significant increase in absence of stratification (all p < 0.001, α = 0.05). These results have implications for characterization, monitoring, and modeling sediment and water interaction as related to eutrophication, as well as to contaminant exposure and bioaccumulation for chemicals within Lake Michigan and large water bodies where stratification of the sediment based upon physics of the system exists.

The Relationship of the Sapstreak Fungus, <i>Ceratocystis virescens</i>, to Sugar Maple Dieback and Decay in Northern Michigan

Unusually high levels of dieback have recently been reported in sugar maple, Acer saccharum Marsh., in Upper Michigan, and a network of plots was established to determine the extent and factors associated with the dieback. A possible contributor to this dieback is sapstreak disease caused by Ceratocystis virescens (Davidson) Moreau. Unhealthy trees with considerable crown dieback were evaluated across the western Upper Peninsula, MI to determine the prevalence of the sapstreak fungus using a minimally destructive sampling technique. Approximately 8% of 90 trees sampled were sapstreak positive and approximately 10% of trees were positive at one site that had recently been harvested. While the high levels of maple dieback present in these forests appear not to be directly caused by widespread sapstreak disease, the occurrence of sapstreak may be significantly impacting trees at some locations. However, even when present on a low number of trees, the biointeraction of sapstreak and decay rates from other fungi could be important for future tree mortality and value to the forest industry. Therefore, the effect of two sapstreak fungal isolates on the amount of decay caused by two common maple white rot fungi, Trametes versicolor (L.:Fr.) Pilat. And Irpex lacteus (Fr.:Fr.) Fr. was tested in the laboratory. Sugar maple wood blocks were precolonized by two native isolates of C. virescens followed by inoculation and incubation with decay fungi. Mean percent weight loss of blocks by white rot decay fungi ranged from 39% to 55%, but decay rates were not significantly affected by the presence of the sapstreak fungus.

Peer Influence of Non-Industrial Private Forest Owners in the Western Upper Peninsula of Michigan

Understanding how non-industrial private forest (NIPF) owners gain and share information regarding the management of their property is very important to policy makers, yet our knowledge regarding how and to what degree this information flows over privately owned landscapes is limited. The work described here seeks to address this shortfall. Widely administered surveys with close-ended questions may not adequately capture this information flow within NIPF owner communities. This study used open-ended questions in interviews of clusters of NIPF owners to determine whether and to what extent owners in-fluence each other directly (through conversations or referrals to sources of advice) or indirectly (through observation of management). We obtained data from thirty-four telephone interviews with owners of NIPF properties in the Western Upper Peninsula of Michigan, and analyzed the data using open coding. Roughly half of the forest owners we interviewed were influenced either directly or indirectly by other members of their NIPF communities. Reasons for owning forests (such as privacy, hunting and nature recreation, and economics) also influenced owners’ management behaviors and goals. This peer-to-peer flow of information (whether direct or indirect) has significant implications for how to distribute management and programmatic information throughout NIPF owner communities, and how amenable these communities may be to cooperative or cross-boundary programs to achieve ecosystem and landscapescale goals.

Analysis of Historic Pavement and Bridge Conditions and Alternative Funding Levels for the Michigan Department of Transportation

In 1997, MDOT （Michigan Department of Transportation） established an ambitious set of condition targets for its pavements and bridges and the department received increased revenue from a 4-cent-per-gallon increase in the state motor fuels tax to help meet its targets. However, over time, actual revenue was less than what was initially estimated as needed and actual conditions fell short of the target levels. In 2013, MDOT performed an analysis of historic conditions to determine what additional fuel tax revenues would have been required beginning in 1997 to replace bond revenues used to fund pavement and bridge projects from 1997 to 2012 and enable MDOT to meet its condition targets. The analysis concluded that, in addition to the actual increase of 4 cents per gallon, a fuel tax increase of another 10 cents per gallon would have been required in 1997 to replace bond revenue used for pavement and bridges and allow MDOT to meet its condition targets. The analysis results were used to help inform the discussion of Michigan＇s targets asset conditions and funding and demonstrate application of MDOT＇s pavement and bridge management systems for performing historic analyses.

Decreased incidence of febrile neutropenia in Michigan following masking and social distancing orders for the COVID-19 pandemic: A population based cohort study

BACKGROUND It has been theorized that 75%-80%of febrile neutropenia(FN)is caused by endogenous pathogens,while up to 20%of cases are thought to be caused by a viral infection.It is unknown if precautions such as masking and social distancing reduce the risk of FN in susceptible populations.AIM To determine whether coronavirus disease 2019(COVID-19)infection mitigation efforts,namely masking and social distancing,were associated with a reduction in the incidence of FN.METHODS This was a retrospective population based cohort study comparing the incidence of FN in the 13 mo prior to(Year 0)and 13 mo following(Year 1)the public health executive orders(PHEO)in Michigan.Data was queried for all emergency department(ED)visits from April 1,2019 to March 31,2021 from the National Syndromic Surveillance Program,a program which collects data that is voluntarily submitted by approximately 89%of Michigan EDs.The primary study outcome was the incidence of FN as a proportion of ED visits in the 13-mo before and 13-mo after COVID-19 mitigations efforts,namely masking and social distancing.We hypothesized that there would be a significant decrease in the incidence of FN in the period following the PHEO aimed at reducing the spread of the severe acute respiratory syndrome coronavirus 2 virus.RESULTS There was a total of 8979221 total ED visits captured during the study period.In Year 0 there were 5073081 recorded ED visits and 3906140 in Year 1.There was a significant reduction in the proportion of total ED visits with a diagnosis of FN,decreasing 13.3%across periods(0.15%vs 0.13%,P=0.036).In patients with a hematologic malignancy a more impressive reduction in the incidence of FN was evident following PHEO(22%vs 17%,P=0.02).CONCLUSION We found a significant association between social distancing and mask guidelines implemented on a large public scale with decreased rates of FN,particularly in those with a hematologic malignancy.These findings may be useful in the design of future research and recommendations regarding the prevention of FN.

Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population.Posture and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous mechanisms.To effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory signals.The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work.Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults.Insufficient emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance.In the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease.We also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older adults.Lastly,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases.

A review on the best practices in concrete pavement design and materials in wet-freeze climates similar to Michigan

The research presented in this paper aims to identify best practices of design and materials for concrete pavements in wet-freeze climates similar to the Michigan State. For the purposes of this paper, a best practice is a procedure that has been shown by field-validated research or experience to produce improved results and that is established or proposed as a standard suitable for widespread implementation. The local wet-freeze climate makes the requirements for Michigan's pavement system different from many other regions. Wetfreeze climates can result in various concrete pavement distress mechanisms such as thermally-induced cracking, freeze-thaw deterioration, accelerated cracking due to loss of support, frost heave, and material degradation. Therefore, appropriate procedures for design and material selection need to be selected to withstand high precipitation and freezing winter temperatures. Failure to take into account the climatic conditions may lead to inadequate or reduced pavement performance. However, utilizing appropriate techniques and materials could potentially improve the quality and increase the service life of the concrete pavement. Three design methods and five materials have been identified, and examples of their successful performance in wet-freeze climates are provided. In addition, the reasons that give them the superior performance in wet-freeze climates are discussed in detail.

Microstructure Characterization of a Biogenic Shale Gas Formation——Insights from the Antrim Shale,Michigan Basin

Biogenic gas shales,predominantly microbial in origin,form an important class of organicrich shale reservoirs with a significant economic potential.Yet large gaps remain in the understanding of their gas generation,storage,and transport mechanisms,as previous studies have been largely focused on mature thermogenic shale reservoirs.In this study,the pore structure of 18 Antrim Shale samples was characterized using gas adsorption(CO2 and N2).The results show that most of the Antrim Shale samples are rich in organic matter content(0.58 wt.%to 14.15 wt.%),with highest values found in the Lachine and Norwood members.Samples from the Paxton Member,characterized by lower organic content,have smaller micropore surface area and micropore volume but larger meso-macro pore surface area and volume.The deconvolution results of the pore size distribution from the N2 adsorption indicate that all of the tested Antrim Shale samples have similar pore groups.Organic matter in the Antrim Shale hosts micro pores instead of meso-macro pores,while clay minerals host both micro and meso-macro pores.Mineralrelated pores play a primary role in the total porosity.The biogenic Antrim Shale,therefore,has different pore structures from other well-studied thermogenic gas shales worldwide.

C-reactive protein and telomerase reverse transcriptase(TERT)associate with chronic disease markers in a sample from low-income neighborhoods in Detroit,Michigan

Racial and ethnic minorities in economically deprived inner cities experience high rates of chronic diseases compared to neighborhoods with higher socioeconomic status(SES).However,these economically deprived populations are understudied in terms of biomarkers associated with chronic disease risk which include C-reactive protein(CRP),telomerase reverse transcriptase(TERT),and glycosylated hemoglobin(A1C).We examined relationships between CRP and TERT and chronic disease indicators(body mass index[BMI]and A1C)in two lowincome,predominantly African American(AA)neighborhoods in Detroit,Michigan.Sixty-nine adults(43 females,26 males,mean age 46 years[y],standard deviation[SD]=15.9)completed a health survey,anthropometry,and finger stick blood tests.A1C was measured using A1CNow test strips,and CRP and TERT levels were measured using enzyme-linked immunosorbent assay(ELISA)with samples extracted from dried blood spots.We examined CRP(mean=4.9,SD=3.1),TERT(mean=32.5,SD=15.1),and A1C(mean=5.4,SD=1.0)by BMI category.We fitted restricted maximum likelihood regression models to evaluate associations between CRP,TERT,BMI,and A1C,after adjustment for demographics and inclusion of a random effect for the neighborhood.In this predominantly AA sample(91%,63/69),68%had levels of CRP(means=4.8 mg/L,SD=3.0 for AAs;6.4 mg/L,SD=3.9 for all others)indicative of chronic inflammation(CRP greater than 3 mg/L).BMI was significantly associated with CRP(p=0.004)and TERT(p=0.026).TERT levels indicate that being overweight is associated with markers of chromosome remodeling,suggestive of chronic disease.CRP followed a similar trend with overweight individuals having higher inflammation and risk of chronic disease.Our findings warrant further exploration of additional factors that may influence CRP and TERT.Furthermore,examining populations in a more ethnically and/or economically diverse,yet still high proportion minority,sample will fill a knowledge gap in this understudied field.

风浪联合作用下分布式调谐质量阻尼器对海上半潜漂浮式风机的减振控制

海上半潜漂浮式风机在复杂深海环境下产生有害振动会威胁风机的安全性和耐久性,针对该问题并结合美国NREL的5 MW样机的漂浮平台几何结构构造,提出利用分布式调谐质量阻尼器(Tuned Mass Dampers,TMDs),即分别在漂浮平台的3根浮筒中布置TMD,形成等边三角形布置,对随机风浪联合作用下海上半潜漂浮式风机的平台纵摇振动进行控制。为了更好地描述分布式TMDs对海上半潜漂浮式风机的减振效果,基于拉格朗日方程和模态叠加法,对海上半潜漂浮式风机-TMDs耦合系统提出并建立了9自由度多体动力学模型。基于H_(∞)算法,即以平台纵摇频响函数的峰值为优化目标,对分布式TMDs的参数进行优化设计,优化设计中考虑了3个TMDs之间的耦合关系。对风机-TMDs耦合系统开展了风浪联合作用下的数值模拟,分析了分布式TMDs对平台纵摇响应的减振效果。结果表明:最优设计下的分布式TMDs对海上半潜漂浮式风机平台纵摇振动具有良好的减振性能;在三种不同工况的随机风浪荷载作用下,分布式TMDs对平台纵摇固有频率附近的功率谱密度曲线峰值减振率和标准差减振率能分别达到39%和52%以上。

分布式储能在成都科幻馆的应用

通过电化学储能在2023年第81届世界科幻大会主场馆——成都科幻馆项目的示范应用,重点从应用场景、并网接入电压、接入系统方案、运行策略等方面分析用户侧分布式储能在民用建筑的应用要点。

浅析混凝土的冻融破坏机理

混凝土耐久性决定了建筑结构的安全性与稳定性,并在长期服役过程中起到重要作用,影响其使用寿命。耐久性与混凝土所处的环境密切相关,寒冷地区正负温交变引起的混凝土冻融破坏是导致混凝土耐久性不足的重要原因之一。介绍了混凝土冻融耐久性的两种典型破坏形式,即内部冻胀开裂和表面盐冻剥蚀,包括冻融破坏的特征、常用表征手段以及劣化机理。同时针对非引气混凝土和引气混凝土,普通混凝土和高性能混凝土的冻融破坏机理进行了比较和分析,并针对性介绍了高性能混凝土的冻融破坏特性。

“社会-生态系统”视角下耕地生态系统服务内涵解析与研究框架

耕地是一个典型的半自然、半人工复合生态系统,耕地生态系统服务已然成为耕地资源研究领域的热点和前沿。然而,耕地生态系统服务研究更多遵循“分布格局-生态过程-服务水平-人类福祉”单向级联逻辑,较少关注耕地系统中自然生态与人类社会的交互关系。基于以“资源单元、资源系统、使用者、治理系统”为主体的社会-生态系统一般分析框架,构建了社会-生态系统视角下的耕地生态系统服务分析框架,提出以“背景诊断-交互分析-机制揭示-治理路径”为脉络的耕地生态系统服务管理研究的理论逻辑与研究框架,有助于阐明耕地生态子系统与社会子系统交互过程中的生态系统服务供需和权衡关系及其与人类福祉的相互影响,揭示处于社会-生态系统中的以耕地生态系统服务为抓手的耕地生态系统演化与发展的因果机制、反馈机制,进而丰富耕地生态系统服务的人地关系理论,为促进耕地多功能保护、实现耕地资源可持续发展提供理论参考和实践借鉴。

焊接结构随机振动疲劳分析方法研究与应用

针对焊接结构在服役过程中承受的随机动载荷频率与结构固有模态频率接近时,接头可能发生疲劳破坏,使传统单轴静载疲劳分析方法不再适用的问题,提出评估焊接结构的多轴随机振动疲劳分析方法。该方法将时域激励信号转化为自谱和互谱,并结合模态分解与结构应力方法,得到包括结构正应力与剪应力的自谱和互谱,基于路径依赖的最大范围法原理得到等效结构应力的功率谱,最后通过Dirlik模型计算出结构损伤和振动疲劳寿命。以某高速货车为例进行疲劳寿命分析与改进校核,验证了该方法可进一步提升焊接结构疲劳寿命预测的时效性和准确性。

微机械频率梳动力学行为及应用研究综述

光学频率梳在精确测量和时频标准领域有着重要作用.随着技术进步,传统的光学频率梳向着小型化、集成化方向发展出微型光学频率梳、微型光机械耦合频率梳等新型技术.借鉴光子和声子之间的共性,纯粹基于机械振动的微机械频率梳为传感器技术、量子信息通信和极端环境下的应用提供了新的可能性.本文首先介绍了微机械频率梳的形成机理和数值仿真模型.在此基础上,本文主要阐述了微机械频率梳基于参数激励、内共振、碰撞效应、负耗散、负非线性摩擦等多种激发原理,总结了国内外现有的研究现状.此外,本文还从实际应用的角度让读者进一步了解微机械频率梳在相关领域的广泛应用,有助于了解微机械频率梳的自身特点和优势.最后,本文对未来发展方向进行了总结和展望.

定容燃烧弹内闪沸燃烧研究

闪沸喷雾作为一种相变喷雾形式,在替代燃料和零碳燃料的燃烧方面具有重要意义。然而当前的研究大部分集中在喷雾形态研究上,对燃烧机理的研究较少。故本文使用定容燃烧弹对稀薄条件下的闪沸喷雾雾化和燃烧过程进行分析,重点研究闪沸喷雾特性、混合气着火特性、火焰传播特性和燃烧放热特性。结果表明,闪沸喷雾能有效降低着火延迟,提升火焰传播速度,从而有利于能量转换,实现更高的放热率和更高的放热量。并且闪沸喷雾火焰前端形状更加规则,表明更加稳定的火焰传播,有助于提升发动机的热效率和稀燃条件下的燃烧稳定性。

活动期糖尿病夏科神经性骨关节病诊疗指南——《国际糖尿病足工作组:糖尿病相关的足病预防与管理指南(2023)》的一部分

国际糖尿病足工作组(IWGDF)自1999年以来发布了糖尿病足病预防和治疗的循证指南。这是IWGDF发布的第一部关于糖尿病患者活动期夏科神经性骨关节病诊断和治疗的指南。我们遵循GRADE方法,以人群-评估-比较-结局(PACO)和人群-干预-比较-结局(PICO)的格式设计临床问题,系统检索医学文献,并提出有依据的推荐。这些推荐是基于我们系统综述的证据,如无证据则参考专家意见,并考虑到与干预相关的受益和危害、患者偏好、可行性和适用性以及成本的权衡。我们在本章节介绍了2023年糖尿病患者活动期夏科神经性骨关节病的诊断和治疗指南,并提出了未来的关键研究方向。

OptoGPT: A foundation model for inverse design in optical multilayer thin film structures

Optical multilayer thin film structures have been widely used in numerous photonic applications.However,existing inverse design methods have many drawbacks because they either fail to quickly adapt to different design targets,or are difficult to suit for different types of structures,e.g.,designing for different materials at each layer.These methods also cannot accommodate versatile design situations under different angles and polarizations.In addition,how to benefit practical fabrications and manufacturing has not been extensively considered yet.In this work,we introduce OptoGPT(Opto Generative Pretrained Transformer),a decoder-only transformer,to solve all these drawbacks and issues simultaneously.