3,001 research outputs found

    Success factors for farming collectives

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    As the most intensive form of partnership in agriculture, farming collectives (FCs) place high demands on their participants. Based on a census of Swiss farming collectives, three success indicators are formed. The first and second describe interpersonal and economic success respectively, whilst the third encompasses overall success. Factors influencing success are determined by means of multiple regressions. Five predictor variables (compatibility with co-operation partner, trust, information quality, attitude of social environment, and relationship/kinship circle of the cooperation partner) accounted for 44 per cent of the variance in interpersonal success. Economic success was far more difficult to explain (R2 = 0.11). Even so, the influence of “soft” factors, even on the economic success of a farming collective, is striking. Above all, trust and the human and structural compatibility of the cooperation partners play an important role for all three types of success. The co-operation agreement, agricultural consultation, the number of participating people on the farm, and the investments made may be ranked as less important than previously assumed.farming collective, economic satisfaction, interpersonal conflicts, Agribusiness,

    CW and pulsed electrically detected magnetic resonance spectroscopy at 263 GHz/12 T on operating amorphous silicon solar cells

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    Here we describe a new high frequency/high field continuous wave and pulsed electrically detected magnetic resonance (CW EDMR and pEDMR) setup, operating at 263 GHz and resonance fields between 0 and 12 T. Spin dependent transport in illuminated hydrogenated amorphous silicon p-i-n solar cells at 5 K and 90 K was studied by in operando 263 GHz CW and pEDMR alongside with complementary X-band CW EDMR. Benefiting from the superior resolution at 263 GHz, we were able to better resolve EDMR signals originating from spin dependent hopping and recombination processes. 5 K EDMR spectra were found to be dominated by conduction and valence band tale states involved in spin dependent hopping, with additional contributions from triplet exciton states. 90 K EDMR spectra could be assigned to spin pair recombination involving conduction band tail states and dangling bonds as dominating spin dependent transport process, with additional contributions from valence band tail and triplet exciton states.Comment: 8 pages, 4 figure

    Transport and recombination through weakly coupled localized spin pairs in semiconductors during coherent spin excitation

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    Semi-analytical predictions for the transients of spin-dependent transport and recombination rates through localized states in semiconductors during coherent electron spin excitation are made for the case of weakly spin-coupled charge carrier ensembles. The results show that the on-resonant Rabi frequency of electrically or optically detected spin-oscillation doubles abruptly as the strength of the resonant microwave field gamma B_1 exceeds the Larmor frequency separation within the pair of charge carrier states between which the transport or recombination transition takes place. For the case of a Larmor frequency separation of the order of gamma B_1 and arbitrary excitation frequencies, the charge carrier pairs exhibit four different nutation frequencies. From the calculations, a simple set of equations for the prediction of these frequencies is derived

    Acceptance and compliance with external hip protectors: A systematic review of the literature

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    Hip fractures may be prevented by the use of external hip protectors, but compliance is often poor. Therefore, the objective of this study was to assess the determinants of compliance with hip protectors by systematically reviewing the literature. A literature search was performed in PubMed, Embase and the Cochrane Library. Primary acceptance with hip protectors ranged from 37% to 72% (median 68%); compliance varied between 20% and 92% (median 56%). However, in most studies it was not very clear how compliance was defined (e.g., average wearing time on active days and during waking hours, number of user-days per all available follow-up days, percentage falls with hip protector) and how it was measured. To provide more insight in the compliance percentages, the different methods of defining and measuring compliance were presented for the selected studies, when provided. Because of the heterogeneity in study design of the selected studies and the lack of quantitative data in most studies, results regarding the determinants of compliance could not be statistically pooled. Instead a qualitative summary of the determinants of compliance was given. The reasons most frequently mentioned for not wearing hip protectors, were: not being comfortable (too tight/poor fit); the extra effort (and time) needed to wear the device; urinary incontinence; and physical difficulties/illnesses. In conclusion, compliance is a very complex, but important issue in hip protector research and implementation. Based on the experiences of elderly people who wear the hip protectors, adjustments should be made to the protector and the underwear, while maintaining the force attenuation capacity. Furthermore, methods to improve the compliance should be developed, and their effectiveness tested. (aut.ref.

    Sentinel Node Detection in Patients with Thyroid Carcinoma: A Meta-analysis

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    Objective: This study was designed to review the diagnostic performance of sentinel node (SN) detection for assessment of the nodal status in thyroid carcinoma patients and to determine the technique (using blue dye or Technetium-99m colloid (99mTc)) that demonstrated the highest success rate with regard to the detection rate and sensitivity. Methods A comprehensive computer literature search of studies published in English language through December 2007 and regarding SN procedures in patients with thyroid disorders was performed in MEDLINE. Pooled values regarding the SN detection rate and the pooled sensitivity values of the SN procedure were presented with a 95% confidence interval (CI) for the different SN detection techniques. Results: Ultimately, we identified 14 studies comprising a total of 457 patients. Of these, ten studies (n = 329 patients) used the blue dye technique with a pooled SN detection of 83% (95% CI, 79–87%). The remaining four studies (n = 128) used 99mTc-colloid with a pooled SN detection of 96% (95% CI, 91–99%; p\0.05 vs. blue dye technique). Conclusion: In patients with suspected thyroid carcinoma, SN biopsy demonstrated a higher SN detection rate when 99mTc was used (96%) instead of the blue dye technique (83%)

    Methodological challenges in following up patients of a hospital child protection team: is there a recruitment bias?

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    BACKGROUND: The aims of this study are to describe the methodological challenges in recruiting a follow-up sample of children referred to an interdisciplinary hospital child protection team (CPT) and to compare participating versus non-participating groups on several demographic variables and maltreatment characteristics. METHODS: Of the 319 in- and outpatients referred to the CPT at University Children's Hospital Zurich from 2005-2006 a sample of 180 children was drawn to contact for a follow-up. The children and their parents were asked to participate in a face-to-face interview at the hospital; in 42 cases the children and parents consented to do so. Alternatively, the parents could take part in a telephone interview (n = 39). Non-participation resulted because no contact or adequate communication in German, French, or English could be established (n = 49) or because the parents or children refused to participate (n = 50). RESULTS: Participants and non-participants did not differ significantly in mean child age at follow-up, gender, family status, place of residence, certainty and type of maltreatment, and type of perpetrator. However, the child's nationality had a significant impact: Percentages of foreign nationals were higher in the fully participating group (45%; n = 19) and the non-contactable group (53%; n = 26) and significantly lower in the refusal (26%; n = 10) and the telephone interview group (18%; n = 9). Although a high percentage of families had moved in the few years since the CPT intervention (32%; n = 57), the percentage of moves was not significantly higher in non-participants compared to participants. CONCLUSIONS: Further research is needed to support these results in different national backgrounds and to test for biases in variables not included - especially socioeconomic status. This includes gathering more detailed information on non-participants, while respecting ethical boundaries. Overall, the fact that only child's nationality was unevenly distributed between participants and non-participants is encouraging

    Sentinel Node Detection in Patients with Thyroid Carcinoma: A Meta-analysis

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    Objective: This study was designed to review the diagnostic performance of sentinel node (SN) detection for assessment of the nodal status in thyroid carcinoma patients and to determine the technique (using blue dye or Technetium-99m colloid
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