Characteristics Of Years Research Articles

Biochemical value of table grape varieties when grown in the Northern Steppe of Ukraine

The study of the possibilities of using the existing biodiversity of table grape varieties to meet the usefulness of the human diet is a key component of improving the existing cultivation of fruit products within the framework of modern agricultural development strategies. The purpose of the study was to establish the possibilities of meeting the needs of the population for valuable nutritional elements based on traditional table grape varieties, which are mainly introduced in the region at the level of small farms and household plots. Five table grape varieties – Arcadia, Nadezhda AZOS, Preobrazhenie, Rumeyka, Dubovsky pink – were investigated for the content of calcium, phosphorus, sulphur, magnesium, potassium, zinc, copper, selenium, manganese, glucose, dietary fibre, vitamins A, C, E, PP, and the dependence on the factors of the year and variety, their interaction, and the classifying ability of features in the space of canonical functions were calculated. The presence of minerals was analysed by atomic emission spectrometry, glucose – by sugar meter, dietary fibre – by enzymatic gravimetric method, vitamins – by fluorometric method, and vitamin C – by titrometric analysis. The possibilities of traditional table grape varieties in meeting the needs for basic valuable food elements are shown and a conclusion is made about the possibilities of selecting appropriate forms, which in the complex are quite capable of meeting modern requirements in this aspect of agricultural development. A predominantly low variability of the studied traits was revealed, which indicates the good reproducibility of the obtained result and the predominant influence of the genotype on the development of the corresponding trait in conditions of contrasting environmental characteristics of years. It was found that improvement in only one of the signs – the content of vitamin PP – is problematic. The low differentiating ability of varieties of the Dubovsky pink, Preobrazhenie, and Rumeyka group leads to the need for further clarification of the ability of only the first of the varieties to be a component in the proposed complex. It is recommended to grow a complex of varieties Nadezhda AZOS and Dubovsky pink

Evolution of Organ Donation Consent, Retrospective Data on Potential Organ Donors.

Identifying the best practices to obtain consent for organ donation involves several strategies. This retrospective analysis of the activity in the field of organ donation identifies the most critical impediments, of which the refusal of families to donate is one of the most frequently encountered. Our main aim was to determine the factors that negatively influence the activity of organ and tissue donations from brain dead donors and to summarize the total number of potential and actual deceased donors, their yearly characteristics, and the organ and tissue donation types performed. A retrospective descriptive study, covering data from 1 January 2014 to 31 December 2023, was conducted in the intensive care unit of the Emergency Clinical County Hospital of Bihor, a recognized facility engaged in organ donation and transplantation from Romania. All potential and actual deceased donors were included in our research. During a period of 10 years, between 2014 and 2023, of the 488 potential and actual deceased donors, 355 (72.7%) were potential donors and 133 (27.3%) actual deceased donors. From 2014 to 2023, a significant percentage [15.28% (133)] of the total number of actual deceased organ donors registered at the national level (870) were identified by us in the Emergency Clinical County Hospital of Bihor.

Asian American Enclaves and Healthcare Accessibility: An Ecologic Study Across Five States

Access to primary care has been a long-standing priority for improving population health. Asian Americans, who often settle in ethnic enclaves, have been found to underutilize health care. Understanding geographic primary care accessibility within Asian American enclaves can help to ensure the long-term health of this fast-growing population. U.S. Census data from five states (California, Florida, New Jersey, New York, and Texas) were used to develop and describe census-tract level measures of Asian American enclaves and social and built environment characteristics for years 2000 and 2010. The 2-step floating catchment area method was applied to National Provider Identifier data to develop a tract-level measure of geographic primary care accessibility. Analyses were conducted in 2022-2023, and associations between enclaves (versus nonenclaves) and geographic primary care accessibility were evaluated using multivariable Poisson regression with robust variance estimation, adjusting for potential area-level confounders. Of 24,482 census tracts, 26.1% were classified as Asian American enclaves. Asian American enclaves were more likely to be metropolitan and have less poverty, lower crime, and lower proportions of uninsured individuals than nonenclaves. Asian American enclaves had higher primary care accessibility than nonenclaves (adjusted prevalence ratio=1.23, 95% CI=1.17, 1.29). Asian American enclaves in five of the most diverse and populous states in the U.S. had fewer markers of disadvantage and greater geographic primary care accessibility. This study contributes to the growing body of research elucidating the constellation of social and built environment features within Asian American enclaves and provides evidence of health-promoting characteristics of these neighborhoods.

Longitudinal lung function in urban firefighters: A group-based multi-trajectory modelling approach.

Urban firefighters are routinely exposed to both physical and chemical hazards that can negatively impact lung health, but it is unclear if firefighters experience accelerated decline in spirometry parameters due to chronic exposure and acute insults. This study aimed to describe sub-groups of firefighters with differing spirometry trajectories and examine the relationship between the identified trajectories and demographic, lifestyle and occupational characteristics. Data from six waves of the Respiratory Function Measurement and Surveillance for South Australian Metropolitan Fire Service Study (2007-2019) were used to identify spirometry parameter z-score trajectories, using group-based multi-trajectory modelling (GBMTM). Analysis of variance and chi-square statistics were used to assess trajectory group differences in baseline self-reported demographic, lifestyle and occupational characteristics. In the 669 included firefighters, we identified five trajectories for the combination of Forced Expiratory Volume in the first second z-score (FEV1 z), Forced Vital Capacity z-score (FVCz) and the ratio of FEV1 and FVC z-score (FEV1 /FVCz). There were three stable trajectories of low, average and very high lung function and two declining trajectories of average and high lung function. Analysis of subgroup characteristics revealed no significant differences between expected and actual group proportions for the occupational characteristics of years of service and respiratory protection use. Significant differences were seen in respiratory health and body mass index. GBMTM defined distinct, plausible spirometry trajectory sub-groups. Firefighter longitudinal spirometry trajectory group membership was associated with BMI and respiratory disease or symptoms but not with self-reported smoking history or occupational factors.

Health care ethics ECHO: Improving ethical response self-efficacy through sensemaking

In clinical practice, evidence suggests that teaching ethics using normative ethical theory has little influence on the ethical actions of providers in practice. Thus, new training methods are needed that improve clinician response to ethical problems. A sensemaking approach to ethics training has demonstrated promise as an evidence-based pedagogical method to improve ethical reasoning and response. Project ECHO (Extension for Community Health Outcomes) is theoretically linked to improved sensemaking. This study examines the effectiveness of ECHO and training in use of sensemaking approaches to ethical response by clinicians. A quasi-experimental design study using univariate linear regression was used to examine the effect of the three types of ethics training on ethical response self-efficacy scores, while controlling for participant characteristics of years in practice, discipline and sex. We found evidence that training in sensemaking through participation in ECHO promotes improved ethical response self-efficacy of clinicians. However, results also suggest that a traditional ECHO format that does not explicitly introduce sensemaking strategies into the training does not result in the same learning outcomes as measured through an ethical response self-efficacy survey. This study found important preliminary results to support use of sensemaking approaches in clinical ethics training.

Exploring the Relevance and Reliability of Fair Value Accounting

Abstract While the FASB had regarded relevance and reliability as two of the most important qualitative characteristics for years, it replaced reliability with faithful representation revising its Concepts Statement No. 2 in 2010. Even if fair values are relevant for the measurement of assets and liabilities, these figures are not necessarily reliable or verifiable. We believe this point is the central message of Ramanna, K. (2022). Unreliable accounts: How regulators fabricate conceptual narratives to diffuse criticism. Accounting, Economics and Law: A convivium forthcoming. The application of fair value measurement has been substantially extended recently to income recognition of not-for-trading financial instruments and even non-financial assets. Is this extension due to the primacy of relevance over reliability, or the relaxing of requirement for reliability toward faithful representation? Whatever measurement method we use, it is absolutely necessary to construct a system of concepts on which the purpose of measurement should be established. In spite of the fact that any measurement method is a means to intended purposes, if we first chose a particular method and applied it to every situation slavishly, we would become similar to a bogus doctor selling a fake drug as panacea valid for any disease.

Relating teenagers’ science interest network characteristics to later science course enrolment: An analysis of Australian PISA 2006 and Longitudinal Surveys of Australian Youth data

Recently, students’ interest in science has been conceptualized as a network model: the science interest network model (SINM) in which affective, behavioural and cognitive components interact together; building on science interest being a dynamic relational construct. In the current study, we combine the Australian Programme for International Student Assessment (PISA) 2006 and Longitudinal Surveys of Australian Youth 2008 data (N = 4758) to investigate relationships between the network characteristics of Year 10 students with their decision to enrol in a science course in Year 12. Specifically, we identified indicators central to the SINM and tested whether they predicted chemistry, physics and biology course enrolment. Students’ intentions to pursue a science-related study or career (future intentions in science) and their enjoyment of science (science enjoyment) were the most central indicators for all three science courses. Centrality was strongly related to course enrolment ( r = .36–.74), lending support to the validity of network theory in the context of science interest, as central indicators may play an influential role within the network.

The Markov Model of Years to Final Separation from the Labor Force 2012-17: Extended Tables of Central Tendency, Shape, Percentile Points, and Bootstrap Standard Errors

Abstract In this paper, we estimate characteristics of years to final separation from the labor force. We use data for the same time period, the same data set, the same education groups for both genders, and similar recursive methods as in our paper on years of labor force activity (Skoog, Ciecka, and Krueger, 2019). Years of labor market activity are a subset of years to final separation from the labor force, with the latter including any years of inactivity that occur prior to final labor force separation. The last set of extended tables for years to final separation from the labor force appeared in 2003 and was based on 1997-98 data (Skoog and Ciecka, 2003).

PDB21 - COMPARATIVE EFFECTIVENESS OF SGLT2 INHIBITORS IN TYPE II DIABETES DERIVED FROM AN OVERVIEW OF 55 SYSTEMATIC REVIEWS

Various SGLT2 inhibitors have been developed and many systematic reviews (SRs) have been published. Some of them are SRs for individual drugs and others are SRs for SGLT2 class drug. We explore the difference between individual drug SRs and the class drug SRs and compare the risk-benefit among SGLT2 inhibitors from network meta-analysis(NMA). Systematic review articles were retrieved by the Medline database. We collected the characteristics of year published, nationality, meta-analysis(MA) including NMA, cardiovascular (CV) events or not, literature search rigorousness, positive finding or not. These factors and their categories were displayed into multi-dimensional configurations by the correspondence analysis. Classification and regression tree(CART) was also applied for discriminating individual drug SRs from the class drug SRs. A total of 55 systematic review articles related to SGLT2 inhibitors were retrieved from 2012 to 2018. By nationality, there were 20 from China, 12 from US, 23 from others. It included 30 conventional MAs, 15 network MAs, and 10 qualitative SR articles. CV events were dealt with in 10 (18%) most of which were academia initiated. Rigorous literature search was conducted in 13 (24%). There were 23 individual drug SRs (dapagliflozin 9, canagliflozin 7, empagliflozin 7) and 32 class drug SRs. Industry sponsor, weak methodology, non-CV, Chinese trials were closely configurated near individual drug SRs by correspondence analysis. The CART also confirmed that individual drug SRs tended to be industry-sponsored, non-CV, positive in findings, weak in methodology. Regarding the risk-benefit among SGLT2 inhibitors, no apparent difference was found from the NMAs although SRs for canagliflozin have been conducted mostly by China. Individual drug SRs were closely related to those with industry sponsor, non-CV endpoints and weak methodological aspects. There seemed to be no apparent difference among individual SGLT2 inhibitors.

Measurement and analysis of the yearly characteristics of deep-buried phreatic evaporation in a hyper-arid area

Water scarcity is the primary cause of land deterioration, so finding new available water resources is crucial to ecological restoration. We investigated a hyper-arid Gobi location in the Dunhuang Mogao Grottoes in this work wherein the burial depth of phreatic water is over 200m. An air-conditioner was used in a closed greenhouse to condense and measure the yearly amount of phreatic evaporation (PE) from 2010 to 2015. The results shown that the annual quantity of PE is 4.52mm, and that the PE has sinusoidal characteristics. The average PE is 0.0183mmd−1 from March to November. Accordingly, by monitoring the annual changes in soil-air temperature and humidity to a depth of 5.0m, we analyzed the water migration mechanism in the heterothermozone (subsurface zone of variable temperature). The results show that, from March to November, the temperature and absolute humidity (AH) increase. This is due to the flow of solar heat entering the soil — the soil subsequently releases moisture and the soil is in a state of increasing AH so that evaporation occurs. From November to March, the temperature decreases. Now, the soil absorbs water vapor and AH is in a state of decline. Thus, it is temperature alternation in the heterothermozone — due to solar heat transfer — that provides the main driving power for PE. When it drives water vapor to move downwards in the heterothermozone, a small part is reversed upwards and evaporates. Solar radiation intensity dominates the annual sinusoidal PE characteristics.

Lifetime design strategy for binary geothermal plants considering degradation of geothermal resource productivity

This work proposes a lifetime design strategy for binary geothermal plants which takes into account heat resource degradation. A model of the resource temperature and mass flow rate decline over a 30year plant life is developed from a survey of data. The standard approach to optimise a basic subcritical cycle of n-pentane working fluid and select component sizes is used for the resource characteristics in years 1, 7, 15 and 30. The performances of the four plants designed for the different resource conditions are then simulated over the plant life to obtain the best lifetime design. The net present value and energy return on investment are selected as the measures of merit. The production history of a real geothermal well in the Taupo Volcanic Zone, New Zealand, is used as a case study for the lifetime design strategy.The results indicate that the operational parameters (such as mass flow rate of n-pentane, inlet turbine pressure and air mass flow rate) and plant performance (net power output) decrease over the whole plant life. The best lifetime plant design was at year 7 with partly degraded conditions. This condition has the highest net present value at USD 6,894,615 and energy return on investment at 4.15. Detailed thermo-economic analysis was carried out with the aim of improving the plant performance to overcome the resource degradation in two ways: operational parameters adjustments and adaptable designs. The results shows that mass flow rates of n-pentane and air cooling should be adjusted to maintain the performance over the plant life. The plant design can also be adapted by installing a recuperator and reducing the heat transfer area of preheater and vaporizer.

Determination of the Impact of Electronic Health Information Systems upon Medical, Medical Backing and Administrative Business Fields in Al-Kindy Teaching Hospital


 
 
 
 
 Objective(s): To determine the impact of the Electronic Health Information Systems upon medical, medical backing and administrative business fields in Al-Kindy Teaching Hospital and to identify the relationship between such impact and their demographic characteristics of years of employment, place of work, and education. Methodology: A descriptive analytical design is employed through the period of April 25th 2016 to May 28th 2016. A purposive "non- probability" sample of (50) subject is selected. The sample is comprised of (25) medical and medical backing staff and (25) administrative staff who are all involved in related business fields in Al-Kindy Teaching Hospital. A self-report questionnaire, of (68) item, is adopted and developed for the purpose of the present study and it is consisted of (6) subscales that measure the phenomenon underlying the study. The questionnaire is rated and scored on 5-level type Likert scale of strongly agree= 5, agree=4, uncertain= 3, disagree=2, and strongly disagree=1. Internal consistency reliability is determined for the questionnaire through split-half technique and computation of Cronbach's Alpha Correlation Coefficient of (r= 0.96) for the internal scale. Content validity for the questionnaire is determined through panel of (9) experts in the fields of medicine, medical backing, and management. Data are collected through the use of the self-report questionnaire as mean of data collection. Data are analyzed through the application of the descriptive statistical data analysis approach of frequencies, percentages, and computation of total scores, mean of scores and Pearson Correlation Coefficient. Results: The present study indicates that the Electronic Health Information Systems have great impact upon medical, medical backing and administrative business fields. The higher the level of these staff characteristics of years of employment, place of work and education, the greater the impact of the Electronic Health Information Systems. Recommendations: The present study recommends that establishment of a nationwide network for Electronic Health Information Systems by which health care organizations can be connected. Increase all medical, medical backing and administrative staff awareness toward the benefits of using the Electronic Health Information Systems. Further research can be conducted with large sample size, different settings and various characteristics.
 
 
 
 
 
 
 
 

Peculiarities of Multiscale Wind Regime Variability at Coastal Water Area of the North-Eastern Black Sea

Peculiarities of variability of wind regime in the period from 1935 to 2014 are discussed. More detailed analysis of variability of meteorological condition on different scales during the last years (2010−2014) is conducted. Progressive vector diagrams are used for visualization of time series of wind vectors. Changes of prevalent winds from NE to S-E-SE (warm period waves) are reflected on a climatic progressive vector diagram from 1935 to 2014. Maximum wave amplitude on a diagram was registered in a period of 2004– 2006. In 2007–2014, a distinctive feature of the wind regime was a dominance of SE winds during warm and abnormally warm years. Major types of atmospheric processes that give rise to dominating winds are outlined. It is demonstrated that differences of the wind regime during particular years with various temperature characteristics of years and winters are caused by a variability of atmospheric synoptic processes on different scales. Using annual wind diagrams and pictures of temporal wind variability, as well as air and water monthly temperature (observation time every 3 hours), periods of prolonged wind forcing (during several months and during 1−2 decades of every month) are distinguished. Role of the winds of SE bearings with high repeatability during several months in forming of the vertical water structure of coastal zone is demonstrated. Analysis of the results of the experimental data acquired in 2010–2014 (research vessel “Ashamba”) has shown that during stable winds of SE bearings advection of cold intermediate waters from the area of their formation (central divergence zone) to the coastal zone becomes stronger.

Shifting from control to elimination: analysis of malaria epidemiological characteristics in Tengchong County around China-Myanmar border, 2005-2014.

BackgroundTengchong County experienced a decreasing malaria prevalence period in 2005–2014 but the factors contributing to the trend are unclear. Herein, the malaria epidemiological data in years of 2005–2014 were collected and analysed, in order to provide evidence for subsequent effective strategic planning of malaria elimination that may be referenced by other counties with the similar elimination programmes along the China-Myanmar border.MethodsA retrospective study was conducted to explore malaria-endemic characteristics in years 2005–2014 in Tengchong County. All individual cases from a web-based reporting system were reviewed and analysed. Local infections and imported cases were obtained from an annual reporting system.ResultsIn total, 8321 confirmed malaria cases were recorded in this period, and 91.5 % of them were reported during 2005–2010. Plasmodium vivax was the major species (n = 5867, 70.5 %). Most cases (92.9 %) were found in males, mainly in the age group 30–34 years. Only five deaths resulting from Plasmodium falciparum were reported, of which three occurred in 2005. The cases were mainly reported in the townships of Wuhe (18.5 %), Mangbang (12.8 %) and Gudong (9.3 %). In addition, 147 local malaria (1.8 %) and 8174 imported malaria (98.2 %) were observed during 2005–2014. However, the proportion of imported malaria was more than 95 % all the time and no local transmission has been observed since 2013. Moreover, Myanmar was the main imported source, with 716 cases (94.6 %, 716/757) from Myanmar in 2011–2014.ConclusionsTengchong County has made achievements in controlling malaria, with incidence at historically its lowest level. However, imported malaria has increased and poses a great threat to malaria elimination. To achieve the elimination goal and prevent the re-introduction of malaria, surveillance systems need to be well planned and managed to ensure timely case detection and prompt response targeted to the mobile and migrate population at elimination stage.

Determination of the Impact of Electronic Health Information Systems upon Medical, Medical Backing and Administrative Decisions in Al-Kindy Teaching Hospital


 
 
 
 
 Objective(s): To determine the impact of the electronic Health Information Systems upon medical, medical Backing and administrativedecisions in Al-Kindy Teaching Hospital. Methodology: A descriptive analytical design is employed through the period of June 14th 2015 to August 15th 2015. A purposive "non- probability" sample of (50) subject is selected. The sample is comprised of (25) medical and medical backing staff and (25) administrative staff who are all involved in the process of decision making in Al-Kindy Teaching Hospital. A self-report questionnaire, of (68) item, is adopted and developed for the purpose of the present study and it is consisted of (6) subscales that measure the phenomenon underlying the study. The questionnaire is rated and scored on 5-level type Likert scale of strongly agree= 5, agree=4, uncertain= 3, disagree=2, and strongly disagree=1. Internal consistency reliability is determined for the questionnaire through split-half technique and computation of Cronbach's AlphaCorrelation Coefficient of (r= 0.96) for the internal scale. Content validity for the questionnaire is determined through panel of (9) experts in the fields of medicine, medical backing, and management. Data are collected through the use of the self-report questionnaire as mean of data collection. Data are analyzed through the application of the descriptive statistical data analysis approach of frequencies, percentages, and computation of total scores, mean of scores and Pearson Correlation Coefficient. Results:The present study indicates that the Electronic Health Information Systems have great impact upon decisions of medical, medical backing and administrative staff. The higher the level of these staff characteristics of years of employment, place of work and education, the greater the impact of the Electronic Health Information Systems. Recommendations:The present study recommends that establishment of a nationwide network for Electronic Health Information Systems by which health care organizations can be connected. Increase all medical, medical backing and administrative staff awareness toward the benefits of using the Electronic Health Information Systems. Further research can be conducted with large sample size, different settings and various characteristics.
 
 
 
 
 
 
 
 

Pulsed dye laser therapy for infantile hemangiomas: a systemic review and meta-analysis.

Infantile hemangiomas (IH) are common pediatric tumors. This meta-analysis was performed to review the therapeutic efficacy and safety of pulsed dye laser (PDL) in the treatment of IH. Seven databases were searched, including PubMed, OvidSP, Karger, Elsevier, EMBASE, Web of Science and Wiley Online Library. The review collected the characteristics of year of publication, hemangiomas cases, prior treatment, laser parameters, adverse side, pretreatment symptom, and number of response from all articles. A total of 1580 studies were identified, the first round search retrieved 39 articles met inclusion criteria. Of those, only 13 articles with 1529 hemangiomas were included in the meta-analysis. This meta-analysis demonstrated an overall resolution rate of 89.1% with 6.28% incidence of adverse effect. PDL may be the effective modality to decrease the proliferative phase and accelerate rates of involution and resolution with few adverse events.

Tinnitus specifically alters the top-down executive control sub-component of attention: Evidence from the Attention Network Task

Tinnitus can be defined as the perception of noxious disabling internal sounds in the absence of external stimulation. While most individuals with tinnitus show some habituation to these internal sounds, many of them experience significant daily life impairments. There is now convincing evidence that impairment in attentional processes may be involved in tinnitus, particularly by hampering the habituation mechanism related to the prefrontal cortex activity. However, it is thus still unclear whether this deficit is an alteration of alerting and orienting attentional abilities, or the consequence of more general alteration in the executive control of attention. In the present study, 20 tinnitus patients were compared to 20 matched healthy controls using the Attention Network Test, to clarify which attentional networks, among alerting, orienting, and executive networks, show differences between the groups. The results showed that patients with tinnitus do not present a general attentional deficit but rather a specific deficit for top-down executive control of attention. This deficit was highly correlated with patient characteristics of years of tinnitus duration and the frequency of coping strategies employed to alleviate tinnitus distress in daily life. These findings are discussed in terms of recent neurobiological models suggesting that prefrontal cortex activity might especially be related to tinnitus habituation. Therapeutic perspectives focusing both on rehabilitation of the executive control of attention and neuromodulation are also discussed.

Adjunct Faculty Characteristics That May Predict Intention to Integrate Technology Into Instruction

This study examined the demographic factors that predict intention to integrate technology into instruction by community college adjunct faculty. Regression model findings indicated that the demographic characteristics of years of teaching experience, teaching discipline, hours of preparation time, and years of experience using computers were predictors of intention to integrate technology. Other literature-based characteristics such as age, gender, and participation in professional development activities, although not noted predictors in the current study, still warrant further examination to provide additional insight into their potential ability to predict technology use by community college adjunct faculty.

缺镁胁迫对纽荷尔脐橙叶绿素荧光特性的影响

以1年生枳砧纽荷尔脐橙为材料,测定不同叶龄叶片相对叶绿素含量和荧光参数,研究缺镁胁迫对叶片叶绿素合成与荧光特性的影响。结果显示,随着叶位的升高,低镁组和无镁组秋梢叶片(老叶)的相对叶绿素含量、<em>F_v/F_m</em>呈明显增加趋势,而春梢叶片(新叶)的相对叶绿素含量、<em>F_v/F_m</em>差异不显著;随着缺镁胁迫程度的增大,叶片相对叶绿素含量、<em>F_v/F_m</em>、光响应能力(<em>ΔF_v/F_m</em>、<em>qP</em>和<em>rETR</em>)均呈降低趋势,而非光化学淬灭(<em>qN</em>)呈升高趋势,低镁组老叶、新叶及无镁组新叶与对照差异不显著(<em>P</em>>0.05),而无镁组老叶与对照差异显著(<em>P</em><0.05)。表明,缺镁胁迫严重时不仅会导致纽荷尔脐橙老叶光合能力降低,也会导致其新叶光合能力降低;短期缺镁胁迫对老叶光合能力的影响显著大于新叶,而且这种差异随着缺镁程度的增大而呈增大趋势。因此,在夏季高光照条件下缺镁纽荷尔脐橙老叶易发生光抑制,缺镁严重时甚至会产生光伤害,导致叶片早衰。;Magnesium (Mg), an essential nutritional element for citrus growth and development, plays an important role in maintaining chloroplast structure, activating a variety of enzymes and improving crop yield and quality. In recent years, with the increased rate of NPK fertilizer application and the decreased rate of manure application, many Newhall navel orange orchards in Gannan in Jiangxi Province, the south of Hunan Province and the north of Guangxi Province have suffered leaf chlorosis due to Mg deficiency. This has become one of the important factors in the South region impeding the yield and quality of citrus fruit. The purpose of the present study is to explore the influence of Mg deficiency stress on chlorophyll synthesis and the fluorescence characteristics of Newhall navel orange (<em>Citrus sinensis</em> Osbeck) at different foliar ages. The experimental materials were one-year-old Newhall navel orange plants grafted onto trifoliate orange rootstock. The plants were grown in sand:perlite (1:1, v/v) medium and irrigated with deionized water for 24 days to stimulate new root growth. Plants were then irrigated every other day for two months with half-strength Hoagland's nutrient solution containing three Mg concentrations: 0 mmol/L (Mg-deficiency, DM), 0.1 mmol/L (low-Mg, LM) or 1 mmol/L (control) MgSO₄. After Mg deficient treatment for two months, a portable chlorophyll meter (SPAD-502) was used to determine the relative amount of leaf total chlorophyll content at different foliar ages. Simultaneously, using a Pulse-Amplitude-Modulation (PAM-2500) fluorometer, the maximum quantum efficiency of photochemistry in photosystem II in the dark (<em>F_v/F_m</em>) was calculated for the three treatments at different foliar ages. In addition, the rapid light response curves of the leaves were determined <em>in situ</em> with a PAM-2500 fluorometer to obtain the chlorophyll fluorescence characteristic parameters, including the effective quantum yield of photosystem II (<em>ΔF_v/F_m</em>), photochemical quenching (<em>qP</em>), non-photochemical quenching (<em>qN</em>) and relative electron transport rate (<em>rETR</em>). Results from recent studies showed that in low-Mg and Mg-deficient treatments, SPAD readings and <em>F_v/F_m</em> in last year's autumn flush leaves increased remarkably with the rising of leaf position, whereas those in this year's spring flush leaves were not statistically significant among leaf positions. SPAD readings, <em>F_v/F_m</em> and light response ability (<em>ΔF_v/F_m</em>, <em>qP</em>, <em>rETR</em>) decreased as the levels of Mg reduced, but <em>qN</em> increased. For chlorophyll fluorescence characteristics of last year's autumn flush leaves, the Mg-deficient treatment was remarkably different compared with the control, whereas there was no significant difference between the low-Mg treatment and the control. For chlorophyll fluorescence characteristics of this year's spring flush leaves, no significant differences were observed among the low-Mg, Mg-deficiency and control treatments. These findings suggested that Mg deficiency stress caused obvious decrement of photosynthetic capacity in last year's autumn flush leaves, and reduction of photosynthetic capacity in this year's spring flush leaves. In addition, short-term Mg deficiency would have a greater adverse effect on last year's autumn flush leaves depending on the degree of Mg deficiency stress. Therefore, under high irradiance in summer, Mg deficiency would make last year's autumn flush leaves of Newhall navel orange sensitive to photoinhibition. Severe Mg deficiency could even cause light-induced damage leading to the occurrence of premature senility (e.g. chlorosis).

The impact of Medicare's Prospective Payment System on staffing of long-term acute care hospitals

Long-term acute care hospitals (LTACHs) treat patients with complex medical conditions requiring hospital care for extended periods of time. In the last decade, Medicare saw spiraling costs for post-acute care settings. The Balanced Budget Act mandated the use of Prospective Payment System (PPS) for all post-acute care settings including LTACHs. Medicare shifted to PPS for LTACHs in October 2002. This study analyzes the early effect of Medicare's PPS on the staffing intensity of LTACHs. The study uses panel data of measures of hospital and market characteristics in years 2001 through 2004. The impact of the payment mechanism, market, and organizational variables on the staffing intensity of LTACHs is evaluated using fixed-effects (within-groups) regression analysis. The fixed-effects regression models found that Medicare's PPS was associated with higher staffing intensity of the LTACHs in years 2003 and 2004. Market-level per capita income was significantly positively associated with staffing intensity. No secular trend in staffing intensity was found. The concern that the cost containment incentives of PPS would result in lowered staffing levels of LTACHs was not borne out by this study. Further follow-up is required to assess in the longer term the effects of PPS on staffing and quality of care in LTACHs.