bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional relationship between human rolandic oscillations and motor cortical excitability: an MEG study
Authors: Tamura Yohei , Hoshiyama Minoru , Nakata Hiroki , Hiroe Nobuo , Inui Koji , Kaneoke Yoshiki , Inoue Kiyoharu , Kakigi Ryusuke
Published: May 2005

Synchronization and desynchronization of the neural rhythm in the brain play an important role in the orchestration of perception, motor action and conscious experience. Based on the results of electrocorticographic and magnetoencephalographic (MEG) recordings, it has been considered that human rolandic oscillations originate in the anterior bank of the central sulcus (20‐Hz rhythm) and the postcentral cortex (10‐Hz rhythm): the 20‐Hz oscillation is closely related to motor function, while the 10‐Hz rhythm is attributed mainly to sensory function. To test whether the rolandic oscillations are functionally relevant to the motor cortical excitability, we examined effects of 1‐Hz repetitive transcranial magnetic stimulation (rTMS) of the left primary motor cortex (M1) on movement‐related changes of the rolandic oscillations in 12 normal subjects. MEG data recorded during brisk extension of the right index finger in two different sessions (with and without rTMS conditioning) were compared. Motor‐evoked potential (MEP) of the right hand muscle was also measured before and after rTMS to assess the motor cortical excitability. We found that 1‐Hz rTMS over M1 significantly reduced the movement‐related rebound of the 20‐Hz oscillation in association with decreased motor cortical excitability. In particular, movement‐related rebound of the 20‐Hz rhythm was closely tied with motor cortical excitability. These findings further strengthen the notion of functional relevance of 20‐Hz cortical oscillation to motor cortical excitability. In the framework of previous studies, the decrease in movement‐related rebound may be regarded as a compensatory reaction to the inhibited cortical activity.
Anesthetic management of a 9‐year‐old child undergoing resection of a tracheal tumor
Authors: KAWARAGUCHI YOSHITAKA , TANIGUCHI AKIHIRO
Published: May 2005

Primary tracheal tumors in children are rare. We report the anesthetic management of a 9‐year‐old child undergoing resection of a midtracheal tumor obstructing approximately 73% of the tracheal lumen. To prepare for any possible airway emergency during the induction and maintenance of anesthesia, we ascertained preoperatively that a mini‐tracheotomy tube could be inserted at the distal portion of the tracheal lesion. Oxygenation and ventilation were adequately maintained throughout the period of anesthesia. Anesthetic management for tracheal tumor resection should reflect the location of the tumor and the degree of tracheal obstruction.
Geometric Representation of High Dimension, Low Sample Size Data
Authors: Hall Peter , Marron J. S. , Neeman Amnon
Published: May 2005

High dimension, low sample size data are emerging in various areas of science. We find a common structure underlying many such data sets by using a non-standard type of asymptotics: the dimension tends to ∞ while the sample size is fixed. Our analysis shows a tendency for the data to lie deterministically at the vertices of a regular simplex. Essentially all the randomness in the data appears only as a random rotation of this simplex. This geometric representation is used to obtain several new statistical insights.
FOSTERING SUSTAINABLE COMPLEXITY IN THE MICROFINANCE INDUSTRY: WHICH WAY FORWARD?
Authors: Chamlee‐Wright Emily
Published: May 2005

The microfinance movement has gained tremendous popularity over the past 30 years, but it is still far from meeting its full potential. The industry stands at a crossroads between increased commercialisation and increased philanthropic aid. Standard economic discourse does little to resolve the debate. F. A. Hayek's concept of the‘extended order’ sheds new light on how we might understand the future development of microfinance.
IMPLEMENTING PRIVATISATON : SOCIAL CHANGE AS A DISCOVERY PROCESS
Authors: Nott David
Published: May 2005

Philanthropists and social change practitioners have successfully advanced privatisation worldwide over the last three decades. Social change can be thought of as a discovery process in which measures of effectiveness are an invaluable tool for creating transparency and accountability for results. These processes organise knowledge and lead to the invention of better ways of doing things. Examining privatisation as a case study opens a broader consideration of the philanthropic enterprise, including barriers to change, diffusion of innovation, and the use of products to lead change. An examination of the processes which led to privatisation also shows how entrepreneurial philanthropy has promoted privatisation.
ROTARIANS AGAINST MALARIA: PHILANTHROPIC ENTERPRISE IN ACTION
Authors: Zimmerman Drake
Published: May 2005

Action by voluntary agencies to eradicate preventable diseases in Africa demonstrates how entrepreneurship can be combined with philanthropy to achieve results that are far more effective than traditional methods of distributing help through bureaucratic mechanisms.
FREEDOM AND ITS ENEMIES: PROBLEMS OF RE‐ESTABLISHING FREEDOM AND DEMOCRACY IN THE EUROPEAN CONTEXT1
Authors: Klaus Václav
Published: May 2005

The experience of living in non‐free communist societies may have made the people of Eastern Europe particularly sensitive to the weakening and ultimately the loss of freedom. Many see such a process currently taking place in a Europe that increasingly places group rights and entitlements above the rights of individuals. Such a process has been driven by a growing belief in the inevitability of market failure, a desire to use the state for personal gain and a fear of openness, freedom and competition.
Surgical Treatment of Patients with Refractory Migraine Headaches and Intranasal Contact Points
Authors: Behin F , Behin B , Bigal ME , Lipton RB
Published: May 2005

Contact point headaches have been attributed to intranasal contact between opposing mucosal surfaces, resulting in referred pain in the distribution of the trigeminal nerve. In subjects with primary headaches, contact points may be associated with treatment refractoriness. We aimed to assess the benefits of surgical correction in patients with refractory migraine or transformed migraine, and radiographic evidence of contact points in the sinonasal area. We reviewed charts of patients who underwent endoscopic sinus surgery and septoplasty for contact point in the same surgical facility, from October 1998 through August 2003. Subjects eligible for surgery had: (i) refractory migraine (failed to standard pharmacological headache treatments) or refractory transformed migraine; (ii) contact points demonstrated by computed tomography scan; (iii) reported significant headache improvement after topical anaesthesia to the contact area. Headache characteristics were assessed preoperatively and at follow-up (6-62 months after surgery) using a standardized questionnaire. A total of 21 subjects (72.5% women) were assessed. Mean headache frequency was reduced from 17.7 to 7.7 headache days per month ( P = 0.003). Mean headache severity was reduced from 7.8 to 3.6 on a 0-10 scale ( P = 0.0001). Headache-related disability was reduced from 5.6 (10-point scale) to 1.8 ( P < 0.0001). A total of 16 subjects (76.2%) had their headache scores improved by 50% or more; nine (42.9%) were pain free at the last follow-up. A total of 18 (95.8%) had at least a 25% reduction in their headache scores. Two patients (9.5%) had increase in their headache score by less than 25%. For selected patients with refractory headaches, demonstrable contact points, and positive response after topical anaesthesia, surgical approach toward the triggering factor may be useful. Prospective studies are necessary to confirm our results.
Validity and Reliability of Turkish Translation of Migraine Disability Assessment (MIDAS) Questionnaire in Patients with Migraine
Authors: Gedikoglu U , Coskun O , Inan LE , Ucler S , Tunc T , Emre U
Published: May 2005

The Migraine Disability Assessment (MIDAS) questionnaire is a brief, self-administered questionnaire which is designed to quantify headache-related disability in a 3-month period. We have tested a Turkish version of the MIDAS questionnaire in 60 migraine patients. Sixty of the clinically diagnosed migraine headache sufferers were enrolled in a 90-day diary study and completed the MIDAS questionnaire in the first, 21st and the last day of the 90-day study. The scores taken from the diary and the scores of the MIDAS taken at different times were evaluated by the correlation tests of both Pearson and Spearman for each question and total scores. Cronbach's scores taken from the diary and taken from the test of the MIDAS which was applied at different times were evaluated. Pearson's correlation on the responses in the initial MIDAS questions was between 0.44 (reduced productivity in household chores) and 0.78 (missed work or school days). The correlation of the Spearman was similar to the Pearson values. As a result, we found that the overall score of the MIDAS has a good reliability and its internal consistency is also good (Cronbach's α 0.87). These findings support the use of the MIDAS questionnaire as a clinical and research tool on Turkish patients.
Comparison of Pre-Headache Phases and Trigger Factors of Migraine and Episodic Tension-Type Headache: Do they Share Similar Clinical Pathophysiology?
Authors: Karli N , Zarifoglu M , Calisir N , Akgoz S
Published: May 2005

Trigger factors, signs and symptoms of the preheadache phases of episodic tension-type headache (ETTH), typical aura with non-migraine headache (TANMH), migraine with (MA) and without aura (MwA) may show similar features. Our objective was to investigate the preheadache phases and trigger factors of these headache types. Questionnaires including trigger factors, signs and symptoms of preheadache phases were answered by all headache patients. A total of 96 patients, 31 ETTH, nine TANMH, 23 MA and 33 MwA patients were included in this study. Analysis of seven groups consisting of 18 individual trigger factors showed that only two groups and five individual trigger factors were significantly different between groups. Hunger and odour were significantly more common in MA, MwA and TANMH patients. Foods were a significant precipitant factor for headache in MA patients. Head and neck movements were important trigger factors in ETTH. In prodrome phase only one out of three groups differed significantly between headache types. Migraine and TANMH patients reported significantly more general signs and symptoms. Analysis of aura signs and symptoms showed that only two out of six groups were significantly more frequent in MA and TANMH patients. Visual aura symptoms were more frequent in MA and TANMH groups, where sensorial auras were reported to be the most frequent in the MA group. Our results showed that different type of headaches share common prodrome and aura signs and symptoms as well as the same trigger factors. We suggest that similar trigger factors may trigger similar mechanisms and may cause common preheadache signs and symptoms in all headache types.
Making information easier for people with learning disabilities
Authors: Rodgers Jackie , Namaganda Syson
Published: May 2005

Accessible summary

Researchers worked with people with learning disabilities to make guidance on how to make information easier. They looked at books and papers and talked to people who had worked at making information easier.

One of the most important things they found out was that everyone who makes information for people with learning disabilities should work with people with learning disabilities to do it.

Everyone needs to keep working to find better ways to make information easier. Information is important for people with learning disabilities to make changes that will make their lives better.

This paper begins with a discussion of what we mean by easy information. It then describes the methods employed in a project to create guidance on making information easier for people with learning disabilities. Researchers and people with learning disabilities worked together to interview information providers about approaches they had used and to carry out a literature review. Draft guidance was written and tested with a range of groups and individuals. Key findings from the project were the necessity of a clear aim when planning information, the need to consider carefully the best format or media for sharing your message and most importantly, to work with your intended audience when creating information. The paper goes on to discuss the importance of making information appropriate for all sections of the community, including people from Black and minority ethnic groups.
The information needs and behaviour of clinical researchers: a user‐needs analysis
Authors: Korjonen‐Close Helena
Published: May 2005

Aims:  As part of the strategy to set up a new information service, including a physical Resource Centre, the analysis of information needs of clinical research professionals involved with clinical research and development in the UK and Europe was required. It also aimed to identify differences in requirements between the various roles of professionals and establish what information resources are currently used.

Methods:  A user‐needs survey online of the members of The Institute. Group discussions with specialist subcommittees of members.

Results:  Two hundred and ninety members responded to the online survey of 20 questions. This makes it a response rate of 7.9%. Members expressed a lack of information in their particular professional area, and lack the skills to retrieve and appraise information.

Discussion:  The results of the survey are discussed in more detail, giving indications of what the information service should collect, what types of materials should be provided to members and what services should be on offer.

Recommendation:  These were developed from the results of the needs analysis and submitted to management for approval. Issues of concern, such as financial constraint and staff constraints are also discussed.

Conclusions:  There is an opportunity to build a unique collection of clinical research material, which will promote The Institute not only to members, but also to the wider health sector. Members stated that the most physical medical libraries don't provide what they need, but the main finding through the survey and discussions is that it's pointless to set up ‘yet another medical library’.
Undertaking an information‐needs analysis of the emergency‐care physician to inform the role of the clinical librarian: a Greek perspective
Authors: Lappa E.
Published: May 2005

Aim of study:  The primary focus of this pilot study was to gain a better understanding of the information needs of emergency‐care clinicians. The secondary focus was to compare the traditional current practice of information provision within other emergency departments in Greek hospitals, with the new model of clinical librarianship (CL).

Rationale:  Clinical staff in the emergency department deal with a variety of cases, they have no time to visit the library, but need information instantly in their place of work. Clinical decision making in the emergency department setting frequently requires the clinician to obtain additional sources of information and clinical librarians may facilitate this.

Study design:  The present study focused on two professional groups: medical librarians (group A) and clinicians (consultants, senior registrars, registrars, nurses (group B), working in the emergency departments of two Greek hospitals. The study was organized through a questionnaire survey and some in‐depth interviews.

Results:  This study showed that, for 100% of the clinicians in daily practice, the main information needs arise while treating patients, and that information would help in making patient‐care decisions. Clinicians made little use of hospital libraries because they are usually under tremendous time pressure. The main outcome of the study was the use of a clinical librarian as an information provider. Clinical librarians supply information to assist decisions, based on this model. This extends the librarian's role in evidence‐based medicine, giving much stronger attention to the relevant evidence in clinical practice.

Conclusions:  Nowadays, health services are facing organizational change. The introduction of new technology, and rapid growth of medical knowledge creates a demand for new ways of providing information. Clinical librarian programmes may deliver patients specific information in a timely manner. The mission of the clinical librarian is to facilitate access to quality information which is necessary for improving health, and to act as an informationist in the emergency department.
Information needs of specialist healthcare professionals: a preliminary study based on the West of Scotland Colorectal Cancer Managed Clinical Network
Authors: Thain Annette , Wales Ann
Published: May 2005

Objectives:  Funded by Research in the Workplace Award (RIWA) 2001, the study investigated the information needs and use of NHS library services by members of the West of Scotland Colorectal Cancer Managed Clinical Network (MCN), a single subject, cross boundary, multi‐professional organization.

Method:  A postal questionnaire sent out in October 2002 was returned by 100 members and follow‐up interviews were held in March 2003 with 11 of the respondents. The questions related to access to resources, library services such as literature searches, current awareness and training. They also explored the use of electronic resources and the Internet.

Results:  Respondents were mainly hospital doctors and a few nurses from across five health boards. Most had access to a library, although not all made use of it, possibly an indication of the need for improved communications between librarians and health‐care staff. Generally, research and professional development were reported as reasons for needing cancer information, but on further investigation the motivation to conduct literature searches was more related to patient care. Examples included treatment of unusual cases, locating information for patients and identifying guidelines. There are indications of unmet needs for local contact information and evaluated patient information.

Conclusion:  Development of a cancer portal within the NHS Scotland e‐Library available from May 2004 based on the Managed Knowledge Network (MKN) concept is attempting to address many of the issues raised in the survey, including inequities of access to services and signposting to a variety of types of information.
Managing knowledge to support the patient journey in NHS Scotland: strategic vision and practical reality
Authors: Wales Ann
Published: May 2005

Background:  The strategy for NHS Scotland Knowledge Services is set in the context of a global transition to a networked model of management within health services.

Objectives:  Development planning for NHS Scotland aims to establish strategic vision and operational delivery systems which meet the needs of this changing health environment.

Methods:  Analysis of knowledge needs at strategic organizational level and through consultation with healthcare staff form the basis of a vision of seamless knowledge support throughout all stages of the patient journey, based on a hybrid model of complementary human‐ and technology‐based knowledge networks.

Results:  The central role of the NHS Scotland e‐library as a system‐wide technology infrastructure facilitating management of both explicit and tacit knowledge is described. The implementation pathway and approaches to evaluation are outlined, based on practical steps to translate the concept of knowledge networks into a working reality.

Conclusions:  The model emerging is that of a knowledge matrix, with the primary delivery system comprising inter‐dependent human, organizational and technology‐based networks focused on the overriding common purpose of improving patient care.
Characteristics of Medical Practices in Three Developed Managed Care Markets
Authors: Landon Bruce E. , Normand Sharon‐Lise T. , Frank Richard , McNeil Barbara J.
Published: May 2005

Objective. To describe physician practices, ranging from solo and two‐physician practices to large medical groups, in three geographically diverse parts of the country with strong managed care presences.

Data Sources/Study Design. Surveys of medical practices in three managed care markets conducted in 2000–2001.

Study Design. We administered questionnaires to all medical practices affiliated with two large health plans in Boston, MA, and Portland, OR, and to all practices providing primary care for cardiovascular disease patients admitted to five large hospitals in Minneapolis, MN. We offer data on how physician practices are structured under managed care in these geographically diverse regions of the country with a focus on the structural characteristics, financial arrangements, and care management strategies adopted by practices.

Data Collection. A two‐staged survey consisting of an initial telephone survey that was undertaken using CATI (computerized assisted telephone interviewing) techniques followed by written modules triggered by specific responses to the telephone survey.

Principal Findings. We interviewed 468 practices encompassing 668 distinct sites of care (overall response rate 72 percent). Practices had an average of 13.9 member physicians (range: 1–125). Most (80.1 percent) medium‐ (four to nine physicians) and large‐size (10 or more physicians) groups regularly scheduled meetings to discuss resource utilization and referrals. Almost 90 percent of the practices reported that these meetings occurred at least once per month. The predominant method for paying practices was via fee‐for‐service payments. Most other payments were in the form of capitation. Overall, 75 percent of physician practices compensated physicians based on productivity, but there was substantial variation related to practice size. Nonetheless, of the practices that did not use straight productivity methods (45 percent of medium‐sized practices and 54 percent of large practices), most used arrangements consisting of combinations of salary and productivity formulas.

Conclusions. We found diversity in the characteristics and capabilities of medical practices in these three markets with high managed care involvement. Financial practices of most practices are geared towards rewarding productivity, and care management practices and capabilities such as electronic medical records remain underdeveloped.
Welfare Reform and Health Insurance of Immigrants
Authors: Kaushal Neeraj , Kaestner Robert
Published: May 2005

Objective. To investigate the effect of the Personal Responsibility and Work Opportunity Reconciliation Act (PRWORA) on the health insurance coverage of foreign‐ and U.S.‐born families headed by low‐educated women.

Data Source. Secondary data from the March series of the Current Population Surveys for 1994–2001.

Study Design. Multivariate regression methods and a pre‐ and post‐test with comparison group research design (difference‐in‐differences) are used to estimate the effect of welfare reform on the health insurance coverage of low‐educated, foreign‐ and U.S.‐born unmarried women and their children. Heterogenous responses by states to create substitute Temporary Aid to Needy Families or Medicaid programs for newly arrived immigrants are used to investigate whether the estimated effect of PRWORA on newly arrived immigrants is related to the actual provisions of the law, or the result of fears engendered by the law.

Principal Findings. PRWORA increased the proportion of uninsured among low‐educated, foreign‐born, unmarried women by 9.9–10.7 percentage points. In contrast, the effect of PRWORA on the health insurance coverage of similar U.S.‐born women is negligible. PRWORA also increased the proportion of uninsured among foreign‐born children living with low‐educated, single mothers by 13.5 percentage points. Again, the policy had little effect on the health insurance coverage of the children of U.S.‐born, low‐educated single mothers. There is some evidence that the fear and uncertainty engendered by the law had an effect on immigrant health insurance coverage.

Conclusions. This research demonstrates that PRWORA adversely affected the health insurance of low‐educated, unmarried, immigrant women and their children. In the case of unmarried women, it may be partly because the jobs that they obtained in response to PRWORA were less likely to provide health insurance. The research also suggests that PRWORA may have engendered fear among immigrants and dampened their enrollment in safety net programs.
The Performance of Administrative and Self‐Reported Measures for Risk Adjustment of Veterans Affairs Expenditures
Authors: Maciejewski Matthew L. , Liu Chuan‐Fen , Derleth Ann , McDonell Mary , Anderson Steve , Fihn Stephan D.
Published: May 2005

Objective. To evaluate the performance of different prospective risk adjustment models of outpatient, inpatient, and total expenditures of veterans who regularly use Veterans Affairs (VA) primary care.

Data Sources. We utilized administrative, survey and expenditure data on 14,449 VA patients enrolled in a randomized trial that gave providers regular patient health assessments.

Study Design. This cohort study compared five administrative data‐based, two self‐report risk adjusters, and base year expenditures in prospective models.

Data Extraction Methods. VA outpatient care and nonacute inpatient care expenditures were based on unit expenditures and utilization, while VA expenditures for acute inpatient care were calculated from a Medicare‐based inpatient cost function. Risk adjusters for this sample were constructed from diagnosis, medication and self‐report data collected during a clinical trial. Model performance was compared using adjusted R2 and predictive ratios.

Principal Findings. In all expenditure models, administrative‐based measures performed better than self‐reported measures, which performed better than age and gender. The Diagnosis Cost Groups (DCG) model explained total expenditure variation (R2=7.2 percent) better than other models. Prior outpatient expenditures predicted outpatient expenditures best by far (R2=42 percent). Models with multiple measures improved overall prediction, reduced over‐prediction of low expenditure quintiles, and reduced under‐prediction in the highest quintile of expenditures.

Conclusions. Prediction of VA total expenditures was poor because expenditure variation reflected utilization variation, but not patient severity. Base year expenditures were the best predictor of outpatient expenditures and nearly the best for total expenditures. Models that combined two or more risk adjusters predicted expenditures better than single‐measure models, but are more difficult and expensive to apply.
Survival Strategies for Michigan's Health Care Safety Net Providers
Authors: Jacobson Peter D. , Dalton Vanessa K. , Berson‐Grand Julie , Weisman Carol S.
Published: May 2005

Objective. To understand key adaptive strategies considered by health care safety net organizations serving uninsured and underinsured populations in Michigan.

Data Sources/Study Setting. Primary data collected through interviews at community‐based free clinics, family planning clinics, local public health departments, and Federally Qualified Health Centers from 2002 to 2003.

Research Design. In each of six service areas in Michigan, we conducted a multiple‐site case study of the four organizations noted above. We conducted interviews with the administrator, the medical or clinical director, the financial or marketing director, and a member of the board of directors. We interviewed 74 respondents at 20 organizations.

Principal Findings. Organizations perceive that unmet need is expanding faster than organizational capacity; organizations are unable to keep up with demand. Other threats to survival include a sicker patient population and difficulty in retaining staff (particularly nurses). Most clinics are adopting explicit business strategies to survive. To maintain financial viability, clinics are: considering or implementing fees; recruiting insured patients; expanding fundraising activities; reducing services; or turning away patients. Collaborative strategies, such as partnerships with hospitals, have been difficult to implement. Clinics are struggling with how to define their mission given the environment and threats to survival.

Conclusions. Adaptive strategies remain a work in progress, but will not be sufficient to respond to increasing service demands. Increased federal funding, or, ideally, a national health insurance program, may be the only viable option for expanding organizational capacity.
Dramatic Improvement of Pyoderma Gangrenosum with Infliximab in a Patient with PAPA Syndrome
Authors: Stichweh Dorothee S. , Punaro Marilynn , Pascual Virginia
Published: May 2005

Abstract:  Infliximab, a chimeric antitumor necrosis factor alpha monoclonal antibody (anti‐TNF α), has been recently shown to have a beneficial effect on pyoderma gangrenosum associated with inflammatory bowel disease. Patients with the syndromic triad of pyogenic sterile arthritis, pyoderma gangrenosum, and acne, an autoinflammatory process caused by mutations in the CD2 binding protein‐1 (CD2BP1) gene, can have severe pyoderma gangrenosum. We describe a 14‐year‐old patient with this syndrome who was unresponsive to multiple therapies. A dramatic improvement in his pyoderma gangrenosum was observed after one infusion of infliximab, and a second infusion led to its resolution. Our observation extends the therapeutic use of infliximab to this component of PAPA syndrome.
Clay‐Turbid Interactions May Not Cascade—A Reminder for Lake Managers
Authors: Horppila Jukka , Liljendahl‐Nurminen Anne
Published: May 2005

Food web management is a frequently used lake restoration method, which aims to reduce phytoplankton biomass by strengthening herbivorous zooplankton through reduction of planktivorous fish. However, in clay‐turbid lakes several factors may reduce the effectivity of food web management. Increasing turbidity reduces the effectivity of fish predation and weakens the link between zooplankton and phytoplankton. Therefore, the effects of fish stock manipulations may not cascade to lower trophic levels as expected. Additionally, in clay‐turbid conditions invertebrate predators may coexist in high densities with planktivorous fish and negate the effects of fish reductions. For instance, in the stratifying regions of the clay‐turbid Lake Hiidenvesi, Chaoborus flavicans is the main regulator of cladocerans and occupies the water column throughout the day, although planktivorous Osmerus eperlanus is very abundant. The coexistence of chaoborids and fish is facilitated by a metalimnetic turbidity peak, which prevents efficient predation by fish. In the shallow parts of the lake, chaoborids are absent despite high water turbidity. We suggest that, generally, the importance of invertebrate predators in relation to vertebrate predators may change along turbidity and depth gradients. The importance of fish predation is highest in shallow waters with low turbidity. When water depth increases, the importance of fish in the top‐down regulation of zooplankton declines, whereas that of chaoborids increases, the change along the depth gradient being moderate in clear‐water lakes and steep in highly turbid lakes. Thus, especially deep clay‐turbid lakes may be problematic for implementing food web management as a restoration tool.
Reestablishing Roots of a Mohawk Community and a Culturally Significant Plant: Sweetgrass
Authors: Shebitz Daniela J. , Kimmerer Robin W.
Published: May 2005

The restoration potential of Sweetgrass (Anthoxanthum nitens (Weber) Y. Schouten & Veldkamp) was evaluated through a field experiment conducted on Kanatsiohareke, a Mohawk farm, and at the LaFayette Experiment Station near Syracuse, New York. The effects of competition reduction and two cover crops on Sweetgrass reestablishment success were examined. Sweetgrass was planted under four treatments: Sweetgrass alone; with existing, old‐field vegetation; with a cover crop of Hairy vetch (Vicia villosa); and with a cover crop of Annual (Italian) ryegrass (Lolium multiflorum). The experiment consisted of five replicates of the four treatments at both LaFayette and Kanatsiohareke. Sweetgrass biomass, height, reproduction rate, and survivorship were greatest in plots that were weeded to eliminate competition and in plots with Hairy vetch as a cover crop. A cover crop of Annual ryegrass resulted in reduced Sweetgrass growth and reproduction. The results of this field experiment indicate that there is great restoration potential for Sweetgrass because it is easily transplanted and reproduces vigorously. For 2.25‐m2 plots, Hairy vetch is an effective cover crop for Sweetgrass. Planting the Sweetgrass with Hairy vetch generated properties of the grass that are desired by basketmakers, such as abundance and tall blades. This technique also allowed for a relatively non–labor intensive method of cultivation. Reestablishment of Sweetgrass offers the members and visitors of Kanatsiohareke the means to continue to use the plant, strengthen traditional practices associated with Sweetgrass, and benefit economically by selling baskets and medicine made with Sweetgrass.
Coastal Dune Forest Development and the Regeneration of Millipede Communities
Authors: Redi Bereket H. , Van Aarde Rudi J. , Wassenaar Theo D.
Published: May 2005

The rehabilitation of disturbed ecosystems through ecological succession should lead to the recovery of indigenous biological assemblages typical of a region. However, rehabilitation may give rise to unusual successional pathways and lead to atypical assemblages. We compared millipede assemblages along a chronosequence of habitats developing in response to a post‐mining coastal dune forest rehabilitation program with those developing spontaneously in the same area. Our comparison suggests that active rehabilitation mimics and even surpasses spontaneous successional development. On both chronosequences, the total number of species, as well as the mean density, diversity, and species richness increased, and dominance decreased, with habitat regeneration age. Moreover, the similarity of millipede assemblages on the two chronosequences to those on three sets of reference sites (mature forests) increased with regeneration age, but this recovery of community composition occurred faster on the rehabilitating chronosequence than on the spontaneously regenerating chronosequence. This suggests that successional processes are leading to a recovery of the predisturbed state, but factors like protection from further disturbances, which occur on the spontaneously regenerating chronosequence, is probably important to ensure success. The distance between a regenerating site and a colonization source area apparently affects the direction of community recovery—assemblages on the rehabilitating chronosequence converged faster onto assemblages on closer reference sites than onto those on reference sites farther away.
Establishing Native Grasses in a Big Sagebrush–Dominated Site: An Intermediate Restoration Step
Authors: Huber‐Sannwald Elisabeth , Pyke David A.
Published: May 2005

Many semiarid rangelands in the Great Basin, U.S.A., are shifting dominance to woody species as a consequence of land degradation including intense livestock grazing and fire suppression. Whereas past rehabilitation efforts in Big sagebrush (Artemisia tridentata) steppes removed the shrub and added introduced forage grasses to successfully shift communities from shrublands to grasslands, current consensus is that native species should be included in restoration projects and that retention of some woody plants is desirable. We examined the potential for interseeding grasses into dense shrub communities as a precursor to thinning shrubs and releasing grasses from shrub interference. We compared seedling establishment of the native grass, Bluebunch wheatgrass (Pseudoroegneria spicata), with that of the Eurasia grass, Crested wheatgrass (Agropyron desertorum), in denseAr. tridentatastands. Shrubs may play an important role as nurse plants for seedling establishment (reduced solar radiation, “island of fertility” effect) but result in highly contrasting light environments and root interference for seedlings. In experimental plots, we examined effects ofAr. tridentatashade levels (0, 40, 70, and 90% reduction of solar radiation) and initial root exclusion (present/absent) on the establishment and growth ofP. spicataandAg. desertorumseedlings. With this design we evaluated the interference effects ofAr. tridentataon the two grasses and identified the most beneficial microsites for grass restoration inAr. tridentata–dominated communities. We predicted seedling survival and growth to be greater under moderate shade (40% reduction) and limited root competition than under no or strong shade conditions (0 and 90%) and unrestricted root interactions. Fifty to 85% of theP. spicataandAg. desertorumseedlings survived the dry summer months of 1995 and 1996 and the intervening winter. Neither shading nor root exclusion fromAr. tridentataaffected final seedling survival of either species. Seedling biomass of both grass species was negatively affected by initial root interactions withAr. tridentata.However, the analysis of seedling biomass variability (coefficient of variation) indicated that in all shade and root‐exclusion treatments, some seedlings of both species developed to large individuals to survive inAr. tridentata–dominated rangelands. Thus, the use of interseeding techniques shows promise for restoring herbaceous species in denseAr. tridentatastands and should be given further consideration when shrub retention is an important consideration.
Implications of Food Web Interactions for Restoration of Missouri Ozark Glade Habitats
Authors: Van Zandt Peter A. , Collins Eboni , Losos Jonathan B. , Chase Jonathan M.
Published: May 2005

Ozark glades are gaps in forested areas that are dominated by grasses and forbs growing in rocky, nutrient‐poor soil. Historically, these open, patchy habitats were maintained by natural and anthropogenic fire cycles that prohibited tree encroachment. However, because of decades of fire suppression, glades have become overgrown by fire‐intolerant species such as Eastern red cedar (Juniperus virginiana). Current restoration practices include cutting down invasive cedars and burning brush piles, which represent habitat for Northern fence lizards (Sceloporus undulatus). Because Sceloporus actively consumes herbivores, we hypothesized that the presence of these lizards in and around brush piles might result in a trophic cascade, whereby damage on native plants is reduced. Field surveys across six Missouri glades indicated that lizard activity was minimal beyond 1 m from habitat structures. This activity pattern reduced grasshopper abundance by 75% and plant damage by over 66% on Echinacea paradoxa and Rudbeckia missouriensis near structures with lizards. A field transplant experiment demonstrated similar reductions in grasshopper abundance and damage on two other glade endemic species, Aster oblongifolius and Schizachyrium scoparium. These results demonstrate that future glade restoration efforts might benefit from considering top‐down effects of predators in facilitating native plant establishment.
Effects of Mycorrhizae and Nontarget Organisms on Restoration of a Seasonal Tropical Forest in Quintana Roo, Mexico: Factors Limiting Tree Establishment
Authors: Allen Michael F. , Allen Edith B. , Gómez‐Pompa Arturo
Published: May 2005

We initiated a study of the effects of mycorrhizal fungal community composition on the restoration of tropical dry seasonal forest trees. Tree seedlings were planted in a severely burned experimental site (1995 fire) during the growing season of 1998 at the El Edén Ecological Reserve, in north Quintana Roo, Mexico. Seedlings ofLeucaena leucocephala,Guazuma ulmifolia,Caesalpinia violacea,Piscidia piscipula,Gliricidia sepium, andCochlospermum vitifoliumwere germinated in steam‐sterilized soil and either remained uninoculated (nonmycorrhizal at transplanting) or were inoculated with mycorrhizal fungi in soils from early‐seral (recently burned) or late‐seral (mature forest) inoculum. Inoculum from the early‐seral soil was largelyGlomusspp., whereas a diverse community of arbuscular mycorrhizal fungi were reintroduced from the mature forest including species ofScutellospora,Gigaspora,Glomus, Sclerocystis, andAcaulospora. Plants grew better when associated with the mature forest inoculum, unlike a previous experiment in which plants grew taller with the early‐seral inoculum. Reasons for the different responses include a less‐intense burn resulting in more residual organic matter. In addition to mycorrhizal responses, plants were severely affected by deer browsing. One tree species,C. vitifoliumfound in the region but not in the reserve, was eliminated by a resident fungal facultative pathogen. Several practical conclusions for restoration can be made. The common nursery practice of soil sterilization may be detrimental because it eliminates beneficial mycorrhizal fungi; species not native to the site may not survive because they may not be adapted to the local pathogens; and herbivory can be severe depending on the landscape context of the restoration.
Forest Restoration in Urbanizing Landscapes: Interactions Between Land Uses and Exotic Shrubs
Authors: Borgmann Kathi L. , Rodewald Amanda D.
Published: May 2005

Preventing and controlling exotic plants remains a key challenge in any ecological restoration, and most efforts are currently aimed at local scales. We combined local‐ and landscape‐scale approaches to identify factors that were most closely associated with invasion of riparian forests by exotic shrubs (Amur honeysuckle [Lonicera maackii] and Tatarian honeysuckle [L. tatarica]) in Ohio, U.S.A. Twenty sites were selected in mature riparian forests along a rural–urban gradient (<1–47% urban land cover). Within each site, we measured percent cover of Lonicera spp. and native trees and shrubs, percent canopy cover, and facing edge aspect. We then developed 10 a priori models based on local‐ and landscape‐level variables that we hypothesized would influence percent cover of Lonicera spp. within 25 m of the forest edge. To determine which of these models best fit the data, we used an information‐theoretic approach and Akaike's information criterion. Percent cover of Lonicera was best explained by the proportion of urban land cover within 1 km of riparian forests. In particular, percent cover of Lonicera was greater in forests within more urban landscapes than in forests within rural landscapes. Results suggest that surrounding land uses influence invasion by exotic shrubs, and explicit consideration of land uses may improve our ability to predict or limit invasion. Moreover, identifying land uses that increase the risk of invasion may inform restoration efforts.
Hydrologic Regime Controls Soil Phosphorus Fluxes in Restoration and Undisturbed Wetlands
Authors: Aldous Allison , McCormick Paul , Ferguson Chad , Graham Sean , Craft Chris
Published: May 2005

Many wetland restoration projects occur on former agricultural soils that have a history of disturbance and fertilization, making them prone to phosphorus (P) release upon flooding. To study the relationship between P release and hydrologic regime, we collected soil cores from three restoration wetlands and three undisturbed wetlands around Upper Klamath Lake in southern Oregon, U.S.A. Soil cores were subjected to one of three hydrologic regimes—flooded, moist, and dry—for 7.5 weeks, and P fluxes were measured upon reflooding. Soils from restoration wetlands released P upon reflooding regardless of the hydrologic regime, with the greatest releases coming from soils that had been flooded or dried. Undisturbed wetland soils released P only after drying. Patterns in P release can be explained by a combination of physical and biological processes, including the release of iron‐bound P due to anoxia in the flooded treatment and the mineralization of organic P under aerobic conditions in the dry treatment. Higher rates of soil P release from restoration wetland soils, particularly under flooded conditions, were associated with higher total P concentrations compared with undisturbed wetland soils. We conclude that maintaining moist soil is the means to minimize P release from recently flooded wetland soils. Alternatively, prolonged flooding provides a means of liberating excess labile P from former agricultural soils while minimizing continued organic P mineralization and soil subsidence.
Removal of Encroaching Conifers to Regenerate Degraded Aspen Stands in the Sierra Nevada
Authors: Jones Bobette E. , Rickman Tom H. , Vazquez Alfred , Sado Yukako , Tate Kenneth W.
Published: May 2005

Aspen is considered a keystone species, and aspen communities are critical for maintaining biodiversity in western landscapes. Inventories of aspen stand health across the Eagle Lake Ranger District (ELRD), Lassen National Forest, California, U.S.A., indicate that 77% of stands are in decline and at risk of loss as defined by almost complete loss of mature aspen with little or no regeneration. This decline is due to competition from conifers establishing within aspen stands as a result of modification of natural fire regimes coupled with excessive browsing by livestock. Restoration treatments were implemented in four aspen stands in 1999 using mechanical equipment to remove competing conifers to enhance the growth environment for aspen. Recruitment and establishment of aspen stems were measured in treated stands (removal of competing conifers) and non‐treated stands (control) immediately prior to treatment and 2 and 4 years post‐treatment. There was a significant increase in total aspen stem density and in two of three aspen regeneration size classes for treated stands compared to controls. Pre‐treatment total aspen density was positively associated with total aspen density and density in all size classes of aspen (p < 0.001). The results demonstrate that mechanical removal of conifers is an effective treatment for restoring aspen.
Importance of Hydrologic and Landscape Heterogeneity for Restoring Bank Swallow (Riparia riparia) Colonies along the Sacramento River, California
Authors: Moffatt Kerry C. , Crone Elizabeth E. , Holl Karen D. , Schlorff Ronald W. , Garrison Barrett A.
Published: May 2005

Human activities have degraded riparian systems in numerous ways, including homogenization of the floodplain landscape and minimization of extreme flows. We analyzed the effects of changes in these and other factors for extinction–colonization dynamics of a threatened Bank Swallow population along the upper Sacramento River, California, U.S.A. We monitored Bank Swallow distributions along a 160‐km stretch of the river from 1986–1992 and 1996–2003 and tested whether site extinctions and colonizations corresponded with changes in maximum river discharge, surrounding land cover, estimated colony size, temperature, and precipitation. Colonization probabilities increased with maximum discharge. Extinction probabilities decreased with proximity to the nearest grassland, decreased with colony size, and increased with maximum discharge. To explore the implications for restoration, we incorporated the statistically estimated effects of distance to grassland and maximum discharge into simple metapopulation models. Under current conditions, the Bank Swallow metapopulation appears to be in continued decline, although stable or increasing numbers cannot be ruled out with the existing data. Maximum likelihood parameters from these regression models suggest that the Sacramento River metapopulation could be restored to 45 colonies through moderate amounts of grassland restoration, large increases in discharge, or direct restoration of nesting habitat by removing approximately 10% of existing bank protection (riprap) from suitable areas. Our results highlight the importance of grassland restoration, mixed benefits of restoring high spring discharge, and the importance of within‐colony dynamics as areas for future research.