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PubMed1997

The Big Ten Student Suicide Study: a 10-year study of suicides on midwestern university campuses.

The Big Ten Student Suicide Study was undertaken from 1980-1990 to determine the suicide rates on Big Ten University campuses. The study design attempted to address many of the statistical and epidemiological flaws identified in previous studies of campus student suicides. The 10-year study collected demographic and correlational data on 261 suicides of registered students at 12 midwestern campuses. The largest number of suicides for both males and females were in the 20-24-year-old age group (46%), and amongst graduate students (32%). The overall student suicide rate of 7.5/100,000 is one half of the computed national suicide rate (15.0/100,000) for a matched sample by age, gender, and race. Despite the overall lower suicide rate, the analyses revealed that students 25 and over have a significantly higher risk than younger students. Although women have rates roughly half those of men throughout their undergraduate years, graduate women have rates not significantly different from their male counterparts (graduate women 9.1/100,000 and graduate men 11.6/100,000).

Adolescent↗
PubMed2025

A large-scale study across the avian clade identifies ecological drivers of neophobia.

Neophobia, or aversion to novelty, is important for adaptability and survival as it influences the ways in which animals navigate risk and interact with their environments. Across individuals, species and other taxonomic levels, neophobia is known to vary considerably, but our understanding of the wider ecological drivers of neophobia is hampered by a lack of comparative multispecies studies using standardized methods. Here, we utilized the ManyBirds Project, a Big Team Science large-scale collaborative open science framework, to pool efforts and resources of 129 collaborators at 77 institutions from 24 countries worldwide across six continents. We examined both difference scores (between novel object test and control conditions) and raw data of latency to touch familiar food in the presence (test) and absence (control) of a novel object among 1,439 subjects from 136 bird species across 25 taxonomic orders incorporating lab, field, and zoo sites. We first demonstrated that consistent differences in neophobia existed among individuals, among species, and among other taxonomic levels in our dataset, rejecting the null hypothesis that neophobia is highly plastic at all taxonomic levels with no evidence for evolutionary divergence. We then tested for effects of ecological factors on neophobia, including diet, sociality, habitat, and range, while accounting for phylogeny. We found that (i) species with more specialist diets were more neophobic than those with more generalist diets, providing support for the Neophobia Threshold Hypothesis; (ii) migratory species were also more neophobic than nonmigratory species, which supports the Dangerous Niche Hypothesis. Our study shows that the evolution of avian neophobia has been shaped by ecological drivers and demonstrates the potential of Big Team Science to advance our understanding of animal behavior.

Animals↗
PubMed2003

DM for complex patients tackles hospital utilization in a big way.

Most DM programs are simply not equipped to handle patients with multiple diagnoses. However, a new Trumbull, CT-based firm has developed a comprehensive intervention that deals exclusively with such patients, with the primary aim of keeping them stabilized and independent in the community. Early data suggests the approach can drastically reduce hospital utilization while relieving the excessive burden such patients place on physician practices.

Chronic Disease↗
PubMed1991

A physiological role for sporadic interruptions of the dopaminergic tone in the genesis of big mass prolactin pulses.

The present studies were designed to evaluate pulsatile PRL secretion after the establishment of either a continuous dopaminergic input or a complete blockade of the dopaminergic inhibitory tone. Adult female rats on estrus and male rats implanted with indwelling jugular cannulae were bled at 3-min intervals for a 3-h period. Bromocriptine (CB-154) and domperidone (DOM) were administered sc and iv, respectively. The administration protocol used for both treatments produced either a continuous dopaminergic input (CB-154 treatment) or a complete dopaminergic blockade (DOM treatment). Pulse analysis was performed on the data series using the algorithm Detect. In both estrous female and male rats, dopaminergic receptor activation by CB-154 reduced peak and trough values, pulse amplitude, area under the pulse, and mean PRL levels. In contrast, a complete dopamine (DA) receptor blockade by DOM increased these parameters. Domperidone treatment increased pulse frequency and reduced pulse interval and duration. Bromocriptine, however, differentially affected some pulsatility parameters depending on the sex of the rats. In females, CB-154 did not alter any of the qualitative parameters (frequency, pulse interval, and duration) of pulsatile PRL secretion. In contrast, in male rats the treatment reduced frequency and duration while increasing pulse interval. CB-154 reduced basal PRL levels in male rats, whereas in estrous females this parameter was not altered. PRL pulses were further evaluated by frequency distribution analysis, using the area under the pulses divided by the baseline to normalize the data due to treatment-induced differences in baselines. This calculation allows the estimation of the amount of hormone released per pulse over the baseline. In both estrous female and male rats, two classes of PRL pulses were identified. One class corresponded to pulses containing a small mass of hormone [small mass pulses (SM)], while the others were characterized by pulses containing a large mass of hormone [big mass pulses (BM)]. Interestingly, both the dopaminergic agonist CB-154 and the dopaminergic antagonist DOM dramatically diminished BM pulse incidence in both estrous female and male rats. In fact, BM pulses were practically absent in both experimental groups. To further substantiate this notion, animals of each experimental group were assigned to one of the following categories: animals depicting BM and SM pulses or rats presenting solely SM pulses.(ABSTRACT TRUNCATED AT 400 WORDS)

Activity Cycles↗
PubMed2006

A multiple criteria analysis for household solid waste management in the urban community of Dakar.

Household solid waste management is a severe problem in big cities of developing countries. Mismanaged solid waste dumpsites produce bad sanitary, ecological and economic consequences for the whole population, especially for the poorest urban inhabitants. Dealing with this problem, this paper utilizes field data collected in the urban community of Dakar, in view of ranking nine areas of the city with respect to multiple criteria of nuisance. Nine criteria are built and organized in three families that represent three classical viewpoints: the production of wastes, their collection and their treatment. Thanks to the method PROMETHEE and the software ARGOS, we do a pair-wise comparison of the nine areas, which allows their multiple criteria rankings according to each viewpoint and then globally. Finding the worst and best areas in terms of nuisance for a better waste management in the city is our final purpose, fitting as well as possible the needs of the urban community. Based on field knowledge and on the literature, we suggest applying general and area-specific remedies to the household solid waste problems.

Belgium↗
PubMed1998

A cross-linguistic comparison of generic noun phrases in English and Mandarin.

Generic noun phrases (e.g. 'bats live in caves') provide a window onto human concepts. They refer to categories as 'kinds rather than as sets of individuals. Although kind concepts are often assumed to be universal, generic expression varies considerably across languages. For example, marking of generics is less obligatory and overt in Mandarin than in English. How do universal conceptual biases interact with language-specific differences in how generics are conveyed? In three studies, we examined adults' generics in English and Mandarin Chinese. The data include child-directed speech from caregivers interacting with their 19-23-month-old children. Examples of generics include: 'baby birds eat worms' (English) and da4 lao3shu3 yao3 bu4 yao3 ren2 ('do big rats bite people or not?') (Mandarin). Generic noun phrases were reliably identified in both languages, although they occurred more than twice as frequently in English as in Mandarin. In both languages, generic usage was domain-specific, with generic noun phrases used most frequently to refer to animals. This domain effect was specific to generics, as non-generic noun phrases were used most frequently for artifacts in both languages. In sum, we argue for universal properties of 'kind' concepts that are expressed with linguistically different constructions. However, the frequency of expression may be influenced by the manner in which generics are expressed in the language.

Adolescent↗
PubMed2025

Expression regulation network in papillae of sea cucumbers: Whole-transcriptome and DNA methylation datasets.

To elucidate the expression regulation network of papilla size of sea cucumbers (Apostichopus japonicus), the whole-transcriptome and DNA methylome datasets of different sizes of papillae in sea cucumbers were generated. Average clean bases of whole-transcriptome (16.35 G) and DNA methylome (28.92 G) were obtained using RNA sequencing and whole-genome bisulfite sequencing techniques. A total of 3,188 ceRNA networks were also identified including 3,081 long non-coding RNAs (lncRNA)/microRNAs (miRNA)/mRNA networks and 107 circular RNA (circRNA)/miRNA/mRNA networks. Methylome data indicate that there were 3,307 and 3,776 differentially methylated regions (DMRs) with high-level methylation as well as 3,125 and 3,016 DMRs with low-level methylation in big papillae compared to small papillae. The identified DMRs were mainly distributed in introns, promotors, or exons. The whole-transcriptome and DNA methylome datasets generated from this study not only established a robust theoretical foundation (especially from the epigenetic aspect) for elucidating expression regulation network determining papilla size in sea cucumbers but also can be a valuable resource of biomarker mining for papilla appearance-based selective breeding in sea cucumbers.

DNA Methylation↗
PubMedDate not supplied

Agents of change: pathways through which mentoring relationships influence adolescents' academic adjustment.

A conceptual model was tested in which the effects of mentoring relationships on adolescents' academic outcomes were hypothesized to be mediated partially through improvements in parental relationships. The parameters of the model were compared with those of an alternative, in which improved parental relationships were treated as an outcome variable rather than a mediator. The study included 959 young adolescents (M age = 12.25 years), all of whom applied to Big Brothers Big Sisters programs. The adolescents were randomly assigned to either the treatment or control group and administered questions at baseline and 18 months later. The hypothesized model provided a significantly better explanation of the data than the alternative. In addition to improvements in parental relationships, mentoring led to reductions in unexcused absences and improvements in perceived scholastic competence. Direct effects of mentoring on global self-worth, school value, and grades were not detected but were instead mediated through improved parental relationships and scholastic competence. Implications of the findings for theory and research are discussed.

Adolescent↗
PubMed2004

Traits and stories: links between dispositional and narrative features of personality.

Dispositional traits and life narratives represent two different levels of personality that have not previously been empirically linked. The current study tested five hypotheses connecting Big-Five traits to life-narrative indices of emotional tone, theme, and structure. Students (Study 1) and adults (Study 2) completed a self-report measure of the Big-Five traits and provided extended written accounts of either ten (students) or eight (adults) key life-narrative scenes, including life high points, low points, and turning points. Content analysis of the narrative data revealed that for both samples Neuroticism was positively associated with an emotionally negative life-narrative tone, Agreeableness was correlated with narrative themes of communion (e.g., friendship, caring for others), and Openness was strongly associated with the structural complexity of life narrative accounts. Contrary to prediction, however, Conscientiousness was not consistently associated with themes of agency (e.g., achievement, self-mastery) and Extraversion was unrelated to positive narrative tone. The results are discussed in the context of contemporary research and theorizing on the narrative study of lives and the relation of narrative research in personality to more conventional, trait-based approaches.

Adolescent↗
PubMed2002

Trends and affordability of cigarette prices: ample room for tax increases and related health gains.

BACKGROUND: Increasing the price of tobacco products is arguably the most effective method of curbing the prevalence and consumption of tobacco products. Price increases would reduce the global burden of disease brought about by tobacco consumption. OBJECTIVES: To compare cigarette price data from more than 80 countries using varying methods, examine trends in prices and affordability during the 1990s, and explore various policy implications pertaining to tobacco prices. DESIGN: March 2001 cigarette price data from the Economist Intelligence Unit are used to compare cigarette prices across countries. To facilitate comparison and to assess affordability, prices are presented in US dollars, purchasing power parity (PPP) units using the Big Mac index as an indicator of PPP and in terms of minutes of labour required to purchase a pack of cigarettes. Annual real percentage changes in cigarette prices between 1990 and 2000 and annual changes in the minutes of labour required to buy cigarettes between 1991 and 2000 are also calculated to examine trends. RESULTS: Cigarette prices tend to be higher in wealthier countries and in countries that have strong tobacco control programmes. On the other hand, minutes of labour required to purchase cigarettes vary vastly between countries. Trends between 1990 and 2000 in real prices and minutes of labour indicate, with some exceptions, that cigarettes have become more expensive in most developed countries but more affordable in many developing countries. However, in the UK, despite recent increases in price, cigarettes are still more affordable than they were in the 1960s. CONCLUSIONS: The results suggest that there is ample room to increase tobacco prices through taxation. In too many countries, cigarette prices have failed to keep up with increases in the general price level of goods and services, rendering them more affordable in 2000 than they were at the beginning of the decade. Opportunities to increase government revenue and improve health through reduced consumption brought about by higher prices have been overlooked in many countries.

Fees and Charges↗
PubMed2002

Selective upregulation of endothelin B receptor gene expression in severe pulmonary hypertension.

BACKGROUND: The pulmonary circulation is an important site for the production and clearance of endothelin (ET)-1, a potent vasoactive and mitogenic peptide. Increased plasma ET-1 levels are observed in pulmonary arterial hypertension (PHT) and may contribute to the regulation of pulmonary vascular resistance, as well as to proliferative changes in the pulmonary vascular bed. METHODS AND RESULTS: We prospectively assessed changes in plasma big ET-1 levels and changes in ET(A) and ET(B) receptor gene expression in 14 consecutive patients undergoing pulmonary thromboendarterectomy for thromboembolic PHT. Plasma big ET-1 levels were higher in patients with PHT (median, 2.2 pg/mL; 25th to 75th percentile, 1.5 to 3.0 pg/mL) compared with age-matched controls (median, 1.2 pg/mL; 25th to 75th percentile, 1.0 to 1.4 pg/mL; P=0.002). In addition to increased plasma big ET-1 levels, selective upregulation of ET(B) receptor mRNA transcripts and immunoreactive protein in the pulmonary artery was observed in the patients; however, ET(A) receptor gene expression was unaffected. CONCLUSIONS: These data suggest that changes in the ET signaling system in PHT caused by thromboembolic disease are not limited to an increased production of ET-1: they also affect ET receptor gene expression.

Endarterectomy↗
PubMed2006

Callous-unemotional traits in a community sample of adolescents.

This study examined the structure, distribution, and correlates of a new measure of self-reported callous-unemotional (CU) traits in 1,443 adolescents (774 boys, 669 girls) between the ages of 13 to 18 years. The Inventory of Callous-Unemotional Traits was subjected to exploratory factor analysis and confirmatory factor analysis. Exploratory factor analysis produced three factors: callousness, uncaring, and unemotional. Fit indexes suggested that the three-factor model, with a single higher-order factor, represented a satisfactory solution for the data. This factor structure fits well for both boys and girls. CU traits correlated significantly with measures of conduct problems and psychosocial impairment. Furthermore, the traits showed predicted associations with sensation seeking and the Big Five personality dimensions, supporting the construct validity of the measure of CU traits.

Adolescent↗
PubMedDate not supplied

Match your sales force structure to your business life cycle.

Although companies devote considerable time and money to managing their sales forces, few focus much thought on how the structure of the sales force needs to change over the life cycle of a product or a business. However, the organization and goals of a sales operation have to evolve as businesses start up, grow, mature, and decline if a company wants to keep winning the race for customers. Specifically, firms must consider and alter four factors over time: the differing roles that internal salespeople and external selling partners should play, the size of the sales force, its degree of specialization, and how salespeople apportion their efforts among different customers, products, and activities. These variables are critical because they determine how quickly sales forces respond to market opportunities, they influence sales reps' performance, and they affect companies' revenues, costs, and profitability. In this article, the authors use timeseries data and cases to explain how, at each stage, firms can best tackle the relevant issues and get the most out of their sales forces. During start-up, smart companies focus on how big their sales staff should be and on whether they can depend upon selling partners. In the growth phase, they concentrate on getting the sales force's degree of specialization and size right. When businesses hit maturity, companies should better allocate existing resources and hire more general-purpose salespeople. Finally, as organizations go into decline, wise sales leaders reduce sales force size and use partners to keep the business afloat for as long as possible.

Commerce↗
PubMedDate not supplied

[Cadmium in the total diet of the typical Italian collective].

An inquiry, by the "Duplicate Portion" technique, has been made to estimate the daily assimilation of cadmium in various collectivities of Rome, representative of different economical-social and sanitary realities. At this regard, 132 complete meals, coming from a hospital canteen, a nursing home for old people, a big company, a community of students and an agricultural firm, have been examined. The sample has been mineralized to white ashes and analyzed in spectrophotometry at A.A. with a little oven of graphite. The data about cadmium assimilation, that we have obtained, are included between 12 and 25 micrograms/day and they are placed at medium-low levels, if we compare then with an assimilation of 15-60 micrograms/day, carried from studies on various populations. No daily data exceeded the limit of tolerability of 57-71 micrograms/day suggested from the W.H.O. Our data, coming the point, do not indicate a particular situation of danger for the groups of population we have studied.

Cadmium↗
PubMed1986

[Evaluation of the efficacy of the surgical treatment of panlobular emphysema].

26 patients presenting with panlobular emphysema between 1978 and 1984 were submitted to a thoracotomy for surgical resection of their bullae. Pre-operative and post-operative evaluations of the following were made: The level of dyspnoea in 5 grades. The FEV1 (VEMS) the forced vital capacity (CVF) the functional residual capacity (CRF) measured plethysmographically, the residual volume (VR), the total lung capacity (CPT). Arterial blood gases. The presence of radiological signs of compression on pulmonary angiography and on plain chest radiographs: an index of compression rated 0 to 6 was defined at the outset. The subjects were split into 3 groups based on their post-operative respiratory function: Group 1: no improvement (n = 7). Group 2: moderate improvement of dyspnoea (n = 11). Group 3: a big improvement in dyspnoea (n = 7). These three groups were homogenous as regards their preoperative respiratory function. On the other hand, the compression caused by the bullae based on the pre-operative radiological data was much greater (p 0.01) in the group of patients who improved. In addition when the index of compression was equal or superior to 3 (n = 14) all the patients were improved (n = 6). The comparison of pre- and post-operative values shows the following results: The change in blood gases was very limited in all groups; the ventilatory parameters were unchanged in group 1; on the other hand in group 2 and 3 one notes an overall improvement in pulmonary function. The size of the improvement however, was very variable from one individual to another.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

[Quantitative relationships in the theory of active transport].

Quantitative relations for the active transport across a membrane are derived according to Mitchell's theory using an approach based on thermodynamic and kinetic principles. The main formula predicts that the flow rate depends on the "oxidative power" of the membrane in case of a big ionic flow. In case of a low current the rate is determined by the redox potential of the respiratory substrate. The relations derived in the paper are in qualitative agreement with Kaback's data on the active transport in bacterial vesicles.

Biological Transport, Active↗
PubMedDate not supplied

Patient satisfaction and the cost/quality equation.

Measuring patient satisfaction with health care treatment and delivery and making necessary adjustments can pay back big dividends to employers, payers, and providers in the form of cost savings and improved quality of care.

Data Collection↗
PubMed1987

Ultrastructural analysis of murine megakaryocyte maturation in vitro: comparison of big-cell and heterogeneous megakaryocyte colonies.

Two morphologically distinct types of murine megakaryocyte (MK) colonies are present after three to seven days in soft agar culture: (a) "big-cell" colonies composed of ten to 30 large, mature-appearing megakaryocytes and (b) "heterogeneous" colonies consisting of approximately 100 or more cells at various stages of differentiation. Cytochemical and immunocytochemical techniques were used to study MK maturation in colonies as well as normal mouse bone marrow. Acetylcholinesterase (AChE), a specific marker for murine platelets and MK, was found in the perinuclear cisterna, endoplasmic reticulum, and occasionally, Golgi cisternae of MK in three-day big-cell colonies and immature bone marrow MK. MK in seven-day big-cell colonies and mature bone marrow MK showed additional reaction sites in the demarcation membrane system and occasional granules. In seven-day heterogeneous colonies, small cells resembled immature bone marrow MK with respect to AChE localization, whereas large cells corresponded to mature bone marrow MK. With immunogold procedures at the ultrastructural level, polyclonal antibodies against human platelet membrane glycoprotein IIIa and antimouse platelet antiserum labeled bone marrow MK and all MK from colonies grown in soft agar cultures for three to seven days. Granulocytes and macrophages in both bone marrow and soft agar cultures were negative for AChE and these immunocytochemical markers. These data indicate that the pattern of expression of AChE during maturation of MK is similar in vivo and in vitro and demonstrate, when using this marker at the fine-structural level, that a greater range of MK maturational stages is present in heterogeneous colonies than is observed in MK in big-cell colonies. Furthermore, we have confirmed that small cells in heterogeneous colonies are MK and that these colonies are composed solely of MK and their precursors.

Acetylcholinesterase↗